linux/arch/mips/bmips/setup.c
Florian Fainelli 466ab2ea23 MIPS: BMIPS: Utilize cfe_die() for invalid DTB
If we were not specified a correct DTB, we will not be able to print
anything useful with panic() which requires a working console of some
sort. Utilize cfe_die() to callback into the CFE default UART and print
some useful diagnostics.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-07-17 14:53:07 +02:00

212 lines
5.0 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
* Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com>
*/
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/memblock.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_clk.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/libfdt.h>
#include <linux/smp.h>
#include <asm/addrspace.h>
#include <asm/bmips.h>
#include <asm/bootinfo.h>
#include <asm/cpu-type.h>
#include <asm/mipsregs.h>
#include <asm/prom.h>
#include <asm/smp-ops.h>
#include <asm/time.h>
#include <asm/traps.h>
#include <asm/fw/cfe/cfe_api.h>
#define RELO_NORMAL_VEC BIT(18)
#define REG_BCM6328_OTP ((void __iomem *)CKSEG1ADDR(0x1000062c))
#define BCM6328_TP1_DISABLED BIT(9)
static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000;
struct bmips_quirk {
const char *compatible;
void (*quirk_fn)(void);
};
static void kbase_setup(void)
{
__raw_writel(kbase | RELO_NORMAL_VEC,
BMIPS_GET_CBR() + BMIPS_RELO_VECTOR_CONTROL_1);
ebase = kbase;
}
static void bcm3384_viper_quirks(void)
{
/*
* Some experimental CM boxes are set up to let CM own the Viper TP0
* and let Linux own TP1. This requires moving the kernel
* load address to a non-conflicting region (e.g. via
* CONFIG_PHYSICAL_START) and supplying an alternate DTB.
* If we detect this condition, we need to move the MIPS exception
* vectors up to an area that we own.
*
* This is distinct from the OTHER special case mentioned in
* smp-bmips.c (boot on TP1, but enable SMP, then TP0 becomes our
* logical CPU#1). For the Viper TP1 case, SMP is off limits.
*
* Also note that many BMIPS435x CPUs do not have a
* BMIPS_RELO_VECTOR_CONTROL_1 register, so it isn't safe to just
* write VMLINUX_LOAD_ADDRESS into that register on every SoC.
*/
board_ebase_setup = &kbase_setup;
bmips_smp_enabled = 0;
}
static void bcm63xx_fixup_cpu1(void)
{
/*
* The bootloader has set up the CPU1 reset vector at
* 0xa000_0200.
* This conflicts with the special interrupt vector (IV).
* The bootloader has also set up CPU1 to respond to the wrong
* IPI interrupt.
* Here we will start up CPU1 in the background and ask it to
* reconfigure itself then go back to sleep.
*/
memcpy((void *)0xa0000200, &bmips_smp_movevec, 0x20);
__sync();
set_c0_cause(C_SW0);
cpumask_set_cpu(1, &bmips_booted_mask);
}
static void bcm6328_quirks(void)
{
/* Check CPU1 status in OTP (it is usually disabled) */
if (__raw_readl(REG_BCM6328_OTP) & BCM6328_TP1_DISABLED)
bmips_smp_enabled = 0;
else
bcm63xx_fixup_cpu1();
}
static void bcm6358_quirks(void)
{
/*
* BCM3368/BCM6358 need special handling for their shared TLB, so
* disable SMP for now
*/
bmips_smp_enabled = 0;
}
static void bcm6368_quirks(void)
{
bcm63xx_fixup_cpu1();
}
static const struct bmips_quirk bmips_quirk_list[] = {
{ "brcm,bcm3368", &bcm6358_quirks },
{ "brcm,bcm3384-viper", &bcm3384_viper_quirks },
{ "brcm,bcm33843-viper", &bcm3384_viper_quirks },
{ "brcm,bcm6328", &bcm6328_quirks },
{ "brcm,bcm6358", &bcm6358_quirks },
{ "brcm,bcm6362", &bcm6368_quirks },
{ "brcm,bcm6368", &bcm6368_quirks },
{ "brcm,bcm63168", &bcm6368_quirks },
{ "brcm,bcm63268", &bcm6368_quirks },
{ },
};
static void __init bmips_init_cfe(void)
{
cfe_seal = fw_arg3;
if (cfe_seal != CFE_EPTSEAL)
return;
cfe_init(fw_arg0, fw_arg2);
}
void __init prom_init(void)
{
bmips_init_cfe();
bmips_cpu_setup();
register_bmips_smp_ops();
}
const char *get_system_type(void)
{
return "Generic BMIPS kernel";
}
void __init plat_time_init(void)
{
struct device_node *np;
u32 freq;
np = of_find_node_by_name(NULL, "cpus");
if (!np)
panic("missing 'cpus' DT node");
if (of_property_read_u32(np, "mips-hpt-frequency", &freq) < 0)
panic("missing 'mips-hpt-frequency' property");
of_node_put(np);
mips_hpt_frequency = freq;
}
void __init plat_mem_setup(void)
{
void *dtb;
const struct bmips_quirk *q;
set_io_port_base(0);
ioport_resource.start = 0;
ioport_resource.end = ~0;
/* intended to somewhat resemble ARM; see Documentation/arm/booting.rst */
if (fw_arg0 == 0 && fw_arg1 == 0xffffffff)
dtb = phys_to_virt(fw_arg2);
else
dtb = get_fdt();
if (!dtb)
cfe_die("no dtb found");
__dt_setup_arch(dtb);
for (q = bmips_quirk_list; q->quirk_fn; q++) {
if (of_flat_dt_is_compatible(of_get_flat_dt_root(),
q->compatible)) {
q->quirk_fn();
}
}
}
void __init device_tree_init(void)
{
struct device_node *np;
unflatten_and_copy_device_tree();
/* Disable SMP boot unless both CPUs are listed in DT and !disabled */
np = of_find_node_by_name(NULL, "cpus");
if (np && of_get_available_child_count(np) <= 1)
bmips_smp_enabled = 0;
of_node_put(np);
}
static int __init plat_dev_init(void)
{
of_clk_init(NULL);
return 0;
}
arch_initcall(plat_dev_init);