leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
Files
b9a0da5b2edcae2a901b85c8cc42efc5bec4bd7b
linux/arch/powerpc/mm/nohash/8xx.c

211 lines
5.3 KiB
C
Raw Normal View History

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 08:55:01 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
powerpc/8xx: Map linear kernel RAM with 8M pages On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:50 +01:00
/*
* This file contains the routines for initializing the MMU
* on the 8xx series of chips.
* -- christophe
*
* Derived from arch/powerpc/mm/40x_mmu.c:
*/
#include <linux/memblock.h>
powerpc/8xx: Add a function to early map kernel via huge pages Add a function to early map kernel memory using huge pages. For 512k pages, just use standard page table and map in using 512k pages. For 8M pages, create a hugepd table and populate the two PGD entries with it. This function can only be used to create page tables at startup. Once the regular SLAB allocation functions replace memblock functions, this function cannot allocate new pages anymore. However it can still update existing mappings with new protections. hugepd_none() macro is moved into asm/hugetlb.h to be usable outside of mm/hugetlbpage.c early_pte_alloc_kernel() is made visible. _PAGE_HUGE flag is now displayed by ptdump. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Change ptdump display to use "huge"] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/68325bcd3b6f93127f7810418a2352c3519066d6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:22 +00:00
#include <linux/hugetlb.h>
powerpc/8xx: Map linear kernel RAM with 8M pages On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:50 +01:00
powerpc/mm: change #include "mmu_decl.h" to <mm/mmu_decl.h> This patch make inclusion of mmu_decl.h independant of the location of the file including it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-29 09:59:59 +00:00
#include <mm/mmu_decl.h>
powerpc/8xx: Map linear kernel RAM with 8M pages On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:50 +01:00
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
#define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)
powerpc/8xx: Ensures RAM mapped with LTLB is seen as block mapped on 8xx. On the 8xx, the RAM mapped with LTLBs must be seen as block mapped, just like areas mapped with BATs on standard PPC32. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12 12:08:45 +02:00
static unsigned long block_mapped_ram;
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
/*
powerpc/8xx: Fix permanently mapped IMMR region. When not using large TLBs, the IMMR region is still mapped as a whole block in the FIXMAP area. Properly report that the IMMR region is block-mapped even when not using large TLBs. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/45f4f414bcd7198b0755cf4287ff216fbfc24b9d.1574774187.git.christophe.leroy@c-s.fr
2019-11-26 13:16:50 +00:00
* Return PA for this VA if it is in an area mapped with LTLBs or fixmap.
powerpc/8xx: Ensures RAM mapped with LTLB is seen as block mapped on 8xx. On the 8xx, the RAM mapped with LTLBs must be seen as block mapped, just like areas mapped with BATs on standard PPC32. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12 12:08:45 +02:00
* Otherwise, returns 0
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
*/
phys_addr_t v_block_mapped(unsigned long va)
{
unsigned long p = PHYS_IMMR_BASE;
if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE)
return p + va - VIRT_IMMR_BASE;
powerpc/8xx: Ensures RAM mapped with LTLB is seen as block mapped on 8xx. On the 8xx, the RAM mapped with LTLBs must be seen as block mapped, just like areas mapped with BATs on standard PPC32. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12 12:08:45 +02:00
if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram)
return __pa(va);
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
return 0;
}
/*
powerpc/8xx: Fix permanently mapped IMMR region. When not using large TLBs, the IMMR region is still mapped as a whole block in the FIXMAP area. Properly report that the IMMR region is block-mapped even when not using large TLBs. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/45f4f414bcd7198b0755cf4287ff216fbfc24b9d.1574774187.git.christophe.leroy@c-s.fr
2019-11-26 13:16:50 +00:00
* Return VA for a given PA mapped with LTLBs or fixmap
* Return 0 if not mapped
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
*/
unsigned long p_block_mapped(phys_addr_t pa)
{
unsigned long p = PHYS_IMMR_BASE;
if (pa >= p && pa < p + IMMR_SIZE)
return VIRT_IMMR_BASE + pa - p;
powerpc/8xx: Ensures RAM mapped with LTLB is seen as block mapped on 8xx. On the 8xx, the RAM mapped with LTLBs must be seen as block mapped, just like areas mapped with BATs on standard PPC32. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12 12:08:45 +02:00
if (pa < block_mapped_ram)
return (unsigned long)__va(pa);
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
return 0;
}
powerpc/8xx: Add a function to early map kernel via huge pages Add a function to early map kernel memory using huge pages. For 512k pages, just use standard page table and map in using 512k pages. For 8M pages, create a hugepd table and populate the two PGD entries with it. This function can only be used to create page tables at startup. Once the regular SLAB allocation functions replace memblock functions, this function cannot allocate new pages anymore. However it can still update existing mappings with new protections. hugepd_none() macro is moved into asm/hugetlb.h to be usable outside of mm/hugetlbpage.c early_pte_alloc_kernel() is made visible. _PAGE_HUGE flag is now displayed by ptdump. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Change ptdump display to use "huge"] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/68325bcd3b6f93127f7810418a2352c3519066d6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:22 +00:00
static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va)
{
if (hpd_val(*pmdp) == 0) {
pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K);
if (!ptep)
return NULL;
hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M);
hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M);
}
return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
}
static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa,
pgprot_t prot, int psize, bool new)
{
mm: pgtable: add shortcuts for accessing kernel PMD and PTE The powerpc 32-bit implementation of pgtable has nice shortcuts for accessing kernel PMD and PTE for a given virtual address. Make these helpers available for all architectures. [rppt@linux.ibm.com: microblaze: fix page table traversal in setup_rt_frame()] Link: http://lkml.kernel.org/r/20200518191511.GD1118872@kernel.org [akpm@linux-foundation.org: s/pmd_ptr_k/pmd_off_k/ in various powerpc places] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-9-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-08 21:33:05 -07:00
pmd_t *pmdp = pmd_off_k(va);
powerpc/8xx: Add a function to early map kernel via huge pages Add a function to early map kernel memory using huge pages. For 512k pages, just use standard page table and map in using 512k pages. For 8M pages, create a hugepd table and populate the two PGD entries with it. This function can only be used to create page tables at startup. Once the regular SLAB allocation functions replace memblock functions, this function cannot allocate new pages anymore. However it can still update existing mappings with new protections. hugepd_none() macro is moved into asm/hugetlb.h to be usable outside of mm/hugetlbpage.c early_pte_alloc_kernel() is made visible. _PAGE_HUGE flag is now displayed by ptdump. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Change ptdump display to use "huge"] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/68325bcd3b6f93127f7810418a2352c3519066d6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:22 +00:00
pte_t *ptep;
if (WARN_ON(psize != MMU_PAGE_512K && psize != MMU_PAGE_8M))
return -EINVAL;
if (new) {
if (WARN_ON(slab_is_available()))
return -EINVAL;
if (psize == MMU_PAGE_512K)
ptep = early_pte_alloc_kernel(pmdp, va);
else
ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va);
} else {
if (psize == MMU_PAGE_512K)
ptep = pte_offset_kernel(pmdp, va);
else
ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
}
if (WARN_ON(!ptep))
return -ENOMEM;
/* The PTE should never be already present */
if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot)))
return -EINVAL;
set_huge_pte_at(&init_mm, va, ptep, pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot)));
return 0;
}
powerpc/8xx: Map linear kernel RAM with 8M pages On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:50 +01:00
/*
* MMU_init_hw does the chip-specific initialization of the MMU hardware.
*/
void __init MMU_init_hw(void)
{
}
powerpc/8xx: Don't set IMMR map anymore at boot Only early debug requires IMMR to be mapped early. No need to set it up and pin it in assembly. Map it through page tables at udbg init when necessary. If CONFIG_PIN_TLB_IMMR is selected, pin it once we don't need the 32 Mb pinned RAM anymore. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/13c1e8539fdf363d3146f4884e5c3c76c6c308b5.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:14 +00:00
static bool immr_is_mapped __initdata;
void __init mmu_mapin_immr(void)
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
{
powerpc/8xx: Don't set IMMR map anymore at boot Only early debug requires IMMR to be mapped early. No need to set it up and pin it in assembly. Map it through page tables at udbg init when necessary. If CONFIG_PIN_TLB_IMMR is selected, pin it once we don't need the 32 Mb pinned RAM anymore. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/13c1e8539fdf363d3146f4884e5c3c76c6c308b5.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:14 +00:00
if (immr_is_mapped)
return;
immr_is_mapped = true;
powerpc/8xx: Map IMMR with a huge page Map the IMMR area with a single 512k huge page. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9495dba06669da40e133f24607758fa6dcc65f66.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:23 +00:00
__early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE,
PAGE_KERNEL_NCG, MMU_PAGE_512K, true);
powerpc/8xx: Map IMMR area with 512k page at a fixed address Once the linear memory space has been mapped with 8Mb pages, as seen in the related commit, we get 11 millions DTLB missed during the reference 600s period. 77% of the misses are on user addresses and 23% are on kernel addresses (1 fourth for linear address space and 3 fourth for virtual address space) Traditionaly, each driver manages one computer board which has its own components with its own memory maps. But on embedded chips like the MPC8xx, the SOC has all registers located in the same IO area. When looking at ioremaps done during startup, we see that many drivers are re-mapping small parts of the IMMR for their own use and all those small pieces gets their own 4k page, amplifying the number of TLB misses: in our system we get 0xff000000 mapped 31 times and 0xff003000 mapped 9 times. Even if each part of IMMR was mapped only once with 4k pages, it would still be several small mappings towards linear area. This patch maps the IMMR with a single 512k page. With this patch applied, the number of DTLB misses during the 10 min period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time hence yet another 10% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:45 +02:00
}
powerpc/8xx: Allow STRICT_KERNEL_RwX with pinned TLB Pinned TLB are 8M. Now that there is no strict boundary anymore between text and RO data, it is possible to use 8M pinned executable TLB that covers both text and RO data. When PIN_TLB_DATA or PIN_TLB_TEXT is selected, enforce 8M RW data alignment and allow STRICT_KERNEL_RWX. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c535fc97bf0dd8693192e25feeed8088701e00c6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:25 +00:00
static void mmu_mapin_ram_chunk(unsigned long offset, unsigned long top,
pgprot_t prot, bool new)
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
{
unsigned long v = PAGE_OFFSET + offset;
unsigned long p = offset;
WARN_ON(!IS_ALIGNED(offset, SZ_512K) || !IS_ALIGNED(top, SZ_512K));
for (; p < ALIGN(p, SZ_8M) && p < top; p += SZ_512K, v += SZ_512K)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
for (; p < ALIGN_DOWN(top, SZ_8M) && p < top; p += SZ_8M, v += SZ_8M)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new);
for (; p < ALIGN_DOWN(top, SZ_512K) && p < top; p += SZ_512K, v += SZ_512K)
__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
if (!new)
flush_tlb_kernel_range(PAGE_OFFSET + v, PAGE_OFFSET + top);
}
powerpc/mm/32: add base address to mmu_mapin_ram() At the time being, mmu_mapin_ram() always maps RAM from the beginning. But some platforms like the WII have to map a second block of RAM. This patch adds to mmu_mapin_ram() the base address of the block. At the moment, only base address 0 is supported. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21 19:08:38 +00:00
unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
powerpc/8xx: Don't use page table for linear memory space Instead of using the first level page table to define mappings for the linear memory space, we can use direct mapping from the TLB handling routines. This has several advantages: * No need to read the tables at each TLB miss * No issue in 16k pages mode where the 1st level table maps 64 Mbytes The size of the available linear space is known at system startup. In order to avoid data access at each TLB miss to know the memory size, the TLB routine is patched at startup with the proper size This patch provides a 10%-15% improvment of TLB miss handling for kernel addresses Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-05-17 09:02:51 +02:00
{
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
unsigned long sinittext = __pa(_sinittext);
powerpc: Enable KFENCE for PPC32 Add architecture specific implementation details for KFENCE and enable KFENCE for the ppc32 architecture. In particular, this implements the required interface in <asm/kfence.h>. KFENCE requires that attributes for pages from its memory pool can individually be set. Therefore, force the Read/Write linear map to be mapped at page granularity. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Marco Elver <elver@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8dfe1bd2abde26337c1d8c1ad0acfcc82185e0d5.1614868445.git.christophe.leroy@csgroup.eu
2021-03-04 14:35:09 +00:00
bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled_or_kfence();
powerpc/8xx: Allow large TLBs with DEBUG_PAGEALLOC DEBUG_PAGEALLOC only manages RW data. Text and RO data can still be mapped with hugepages and pinned TLB. In order to map with hugepages, also enforce a 512kB data alignment minimum. That's a trade-off between size of speed, taking into account that DEBUG_PAGEALLOC is a debug option. Anyway the alignment is still tunable. We also allow tuning of alignment for book3s to limit the complexity of the test in Kconfig that will anyway disappear in the following patches once DEBUG_PAGEALLOC is handled together with BATs. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c13256f2d356a316715da61fe089b3623ef217a5.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:26 +00:00
unsigned long boundary = strict_boundary ? sinittext : etext8;
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
WARN_ON(top < einittext8);
powerpc/8xx: Don't set IMMR map anymore at boot Only early debug requires IMMR to be mapped early. No need to set it up and pin it in assembly. Map it through page tables at udbg init when necessary. If CONFIG_PIN_TLB_IMMR is selected, pin it once we don't need the 32 Mb pinned RAM anymore. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/13c1e8539fdf363d3146f4884e5c3c76c6c308b5.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:14 +00:00
mmu_mapin_immr();
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true);
powerpc: Enable KFENCE for PPC32 Add architecture specific implementation details for KFENCE and enable KFENCE for the ppc32 architecture. In particular, this implements the required interface in <asm/kfence.h>. KFENCE requires that attributes for pages from its memory pool can individually be set. Therefore, force the Read/Write linear map to be mapped at page granularity. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Marco Elver <elver@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8dfe1bd2abde26337c1d8c1ad0acfcc82185e0d5.1614868445.git.christophe.leroy@csgroup.eu
2021-03-04 14:35:09 +00:00
if (debug_pagealloc_enabled_or_kfence()) {
powerpc/8xx: Allow large TLBs with DEBUG_PAGEALLOC DEBUG_PAGEALLOC only manages RW data. Text and RO data can still be mapped with hugepages and pinned TLB. In order to map with hugepages, also enforce a 512kB data alignment minimum. That's a trade-off between size of speed, taking into account that DEBUG_PAGEALLOC is a debug option. Anyway the alignment is still tunable. We also allow tuning of alignment for book3s to limit the complexity of the test in Kconfig that will anyway disappear in the following patches once DEBUG_PAGEALLOC is handled together with BATs. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c13256f2d356a316715da61fe089b3623ef217a5.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:26 +00:00
top = boundary;
} else {
mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true);
mmu_mapin_ram_chunk(einittext8, top, PAGE_KERNEL, true);
}
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
if (top > SZ_32M)
memblock_set_current_limit(top);
block_mapped_ram = top;
return top;
powerpc/8xx: Map linear kernel RAM with 8M pages On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:50 +01:00
}
powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.c Now we have a 8xx specific .c file for that so put it in there as other powerpc variants do Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:54 +01:00
powerpc/8xx: don't disable large TLBs with CONFIG_STRICT_KERNEL_RWX This patch implements handling of STRICT_KERNEL_RWX with large TLBs directly in the TLB miss handlers. To do so, etext and sinittext are aligned on 512kB boundaries and the miss handlers use 512kB pages instead of 8Mb pages for addresses close to the boundaries. It sets RO PP flags for addresses under sinittext. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21 19:08:51 +00:00
void mmu_mark_initmem_nx(void)
{
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
unsigned long sinittext = __pa(_sinittext);
unsigned long boundary = strict_kernel_rwx_enabled() ? sinittext : etext8;
unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
powerpc/32: Call mmu_mark_initmem_nx() regardless of data block mapping. mark_initmem_nx() calls either mmu_mark_initmem_nx() or set_memory_attr() based on return from v_block_mapped() of _sinittext. But we can now handle text and data independently, so that text may be mapped by block even when data is mapped by pages. On the 8xx for instance, at startup 32Mbytes of memory are pinned in TLB. So the pinned entries need to go away for sinittext. In next patch a BAT will be set to also covers sinittext on book3s/32. So it will also be needed to call mmu_mark_initmem_nx() even when data above sinittext is not mapped with BATs. As this is highly dependent on the platform, call mmu_mark_initmem_nx() regardless of data block mapping. Then the platform will know what to do. Modify 8xx mmu_mark_initmem_nx() so that inittext mapping is modified only when pagealloc debug and kfence are not active, otherwise inittext is mapped with standard pages. And don't do anything on kernel text which is already mapped with PAGE_KERNEL_TEXT. Fixes: da1adea07576 ("powerpc/8xx: Allow STRICT_KERNEL_RwX with pinned TLB") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/db3fc14f3bfa6215b0786ef58a6e2bc1e1f964d7.1655202804.git.christophe.leroy@csgroup.eu
2022-06-14 12:34:08 +02:00
if (!debug_pagealloc_enabled_or_kfence())
mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL, false);
powerpc/8xx: Allow STRICT_KERNEL_RwX with pinned TLB Pinned TLB are 8M. Now that there is no strict boundary anymore between text and RO data, it is possible to use 8M pinned executable TLB that covers both text and RO data. When PIN_TLB_DATA or PIN_TLB_TEXT is selected, enforce 8M RW data alignment and allow STRICT_KERNEL_RWX. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c535fc97bf0dd8693192e25feeed8088701e00c6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:25 +00:00
powerpc/8xx: Always pin kernel text TLB There is no big poing in not pinning kernel text anymore, as now we can keep pinned TLB even with things like DEBUG_PAGEALLOC. Remove CONFIG_PIN_TLB_TEXT, making it always right. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Drop ifdef around mmu_pin_tlb() to fix build errors] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/203b89de491e1379f1677a2685211b7c32adfff0.1606231483.git.christophe.leroy@csgroup.eu
2020-11-24 15:24:55 +00:00
mmu_pin_tlb(block_mapped_ram, false);
powerpc/8xx: don't disable large TLBs with CONFIG_STRICT_KERNEL_RWX This patch implements handling of STRICT_KERNEL_RWX with large TLBs directly in the TLB miss handlers. To do so, etext and sinittext are aligned on 512kB boundaries and the miss handlers use 512kB pages instead of 8Mb pages for addresses close to the boundaries. It sets RO PP flags for addresses under sinittext. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21 19:08:51 +00:00
}
#ifdef CONFIG_STRICT_KERNEL_RWX
void mmu_mark_rodata_ro(void)
{
powerpc/8xx: Map linear memory with huge pages Map linear memory space with 512k and 8M pages whenever possible. Three mappings are performed: - One for kernel text - One for RO data - One for the rest Separating the mappings is done to be able to update the protection later when using STRICT_KERNEL_RWX. The ITLB miss handler now need to also handle huge TLBs unless kernel text in pinned. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c44f0ab5510474f25123d904cd1f4e5c6aa3c1ac.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:24 +00:00
unsigned long sinittext = __pa(_sinittext);
mmu_mapin_ram_chunk(0, sinittext, PAGE_KERNEL_ROX, false);
powerpc/8xx: Allow STRICT_KERNEL_RwX with pinned TLB Pinned TLB are 8M. Now that there is no strict boundary anymore between text and RO data, it is possible to use 8M pinned executable TLB that covers both text and RO data. When PIN_TLB_DATA or PIN_TLB_TEXT is selected, enforce 8M RW data alignment and allow STRICT_KERNEL_RWX. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c535fc97bf0dd8693192e25feeed8088701e00c6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:25 +00:00
if (IS_ENABLED(CONFIG_PIN_TLB_DATA))
mmu_pin_tlb(block_mapped_ram, true);
powerpc/8xx: don't disable large TLBs with CONFIG_STRICT_KERNEL_RWX This patch implements handling of STRICT_KERNEL_RWX with large TLBs directly in the TLB miss handlers. To do so, etext and sinittext are aligned on 512kB boundaries and the miss handlers use 512kB pages instead of 8Mb pages for addresses close to the boundaries. It sets RO PP flags for addresses under sinittext. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21 19:08:51 +00:00
}
#endif
powerpc/8xx: mark init functions with __init setup_initial_memory_limit() is only called during init. mmu_patch_cmp_limit() is only called from 8xx_mmu.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-12 12:08:55 +02:00
void __init setup_initial_memory_limit(phys_addr_t first_memblock_base,
phys_addr_t first_memblock_size)
powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.c Now we have a 8xx specific .c file for that so put it in there as other powerpc variants do Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:54 +01:00
{
/* We don't currently support the first MEMBLOCK not mapping 0
* physical on those processors
*/
BUG_ON(first_memblock_base != 0);
powerpc/8xx: Map 32Mb of RAM at init. At the time being, initial MMU setup allows 24 Mbytes of DATA and 8 Mbytes of code. Some debug setup like CONFIG_KASAN generate huge kernels with text size over the 8M limit and data over the 24 Mbytes limit. Here is an 8xx kernel compiled with CONFIG_KASAN_INLINE for one of my boards: [root@po16846vm linux-powerpc]# size -x vmlinux text data bss dec hex filename 0x111019c 0x41b0d4 0x490de0 26984528 19bc050 vmlinux This patch maps up to 32 Mbytes code based on _einittext symbol and allows 32 Mbytes of memory instead of 24. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-13 16:06:21 +00:00
/* 8xx can only access 32MB at the moment */
powerpc/8xx: Always pin TLBs at startup. At startup, map 32 Mbytes of memory through 4 pages of 8M, and PIN them inconditionnaly. They need to be pinned because KASAN is using page tables early and the TLBs might be dynamically replaced otherwise. Remove RSV4I flag after installing mappings unless CONFIG_PIN_TLB_XXXX is selected. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b27c5767d18053b59f7eefddc189fcc3acf7b9c2.1589866984.git.christophe.leroy@csgroup.eu
2020-05-19 05:49:15 +00:00
memblock_set_current_limit(min_t(u64, first_memblock_size, SZ_32M));
powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.c Now we have a 8xx specific .c file for that so put it in there as other powerpc variants do Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:07:54 +01:00
}
powerpc/8xx: rewrite set_context() in C There is no real need to have set_context() in assembly. Now that we have mtspr() handling CPU6 ERRATA directly, we can rewrite set_context() in C language for easier maintenance. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2016-02-09 17:08:18 +01:00
Revert "mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge" This reverts commit c742199a014de23ee92055c2473d91fe5561ffdf. c742199a014d ("mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge") breaks arm64 in at least two ways for configurations where PUD or PMD folding occur: 1. We no longer install huge-vmap mappings and silently fall back to page-granular entries, despite being able to install block entries at what is effectively the PGD level. 2. If the linear map is backed with block mappings, these will now silently fail to be created in alloc_init_pud(), causing a panic early during boot. The pgtable selftests caught this, although a fix has not been forthcoming and Christophe is AWOL at the moment, so just revert the change for now to get a working -rc3 on which we can queue patches for 5.15. A simple revert breaks the build for 32-bit PowerPC 8xx machines, which rely on the default function definitions when the corresponding page-table levels are folded, since commit a6a8f7c4aa7e ("powerpc/8xx: add support for huge pages on VMAP and VMALLOC"), eg: powerpc64-linux-ld: mm/vmalloc.o: in function `vunmap_pud_range': linux/mm/vmalloc.c:362: undefined reference to `pud_clear_huge' To avoid that, add stubs for pud_clear_huge() and pmd_clear_huge() in arch/powerpc/mm/nohash/8xx.c as suggested by Christophe. Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Fixes: c742199a014d ("mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge") Signed-off-by: Jonathan Marek <jonathan@marek.ca> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> [mpe: Fold in 8xx.c changes from Christophe and mention in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/linux-arm-kernel/CAMuHMdXShORDox-xxaeUfDW3wx2PeggFSqhVSHVZNKCGK-y_vQ@mail.gmail.com/ Link: https://lore.kernel.org/r/20210717160118.9855-1-jonathan@marek.ca Link: https://lore.kernel.org/r/87r1fs1762.fsf@mpe.ellerman.id.au Signed-off-by: Will Deacon <will@kernel.org>
2021-07-21 17:02:13 +10:00
int pud_clear_huge(pud_t *pud)
{
return 0;
}
int pmd_clear_huge(pmd_t *pmd)
{
return 0;
}
Reference in New Issue Copy Permalink