Commit Graph

18 Commits

Author SHA1 Message Date
Geert Uytterhoeven
5fc69b6e51 mtd: hyperbus: HBMC_AM654 should depend on ARCH_K3
The AM65x HyperBus controller is only present on Texas Instruments AM65x
SoCs.  Hence add a dependency on ARCH_K3, to prevent asking the user
about this driver when configuring a kernel without support for the
Texas Instruments Inc. K3 multicore SoC architecture.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/9fd6b975adba710158f28aa603cf87a6d189a418.1646655894.git.geert+renesas@glider.be
2022-03-14 17:01:58 +01:00
Linus Torvalds
c01d85c219 MTD core changes:
* mtdchar: Prevent unbounded allocation in MEMWRITE ioctl
 * gen_probe: Use bitmap_zalloc() when applicable
 * Introduce an expert mode for forensics and debugging purposes
 * Clear out unregistered devices a bit more
 * Provide unique name for nvmem device
 * Remove unused header file <linux/mtd/latch-addr-flash.h>
 * Fixed breaking list in __mtd_del_partition.
 
 MTD device changes:
 * sst25l, mchp48l640, mchp23k256, dataflash:
   - Warn about failure to unregister mtd device
 
 Raw NAND core changes:
 * Export nand_read_page_hwecc_oob_first()
 
 GPMC memory controller for OMAP2 NAND controller changes:
 * GPMC:
   - Add support for AM64 SoC and allow build on K3 platforms
   - Use a compatible match table when checking for NAND controller
   - Use platform_get_irq() to get the interrupt
 
 Raw NAND controller changes:
 * OMAP2 NAND controller:
   - Document the missing 'rb-gpios' DT property
   - Drop unused variable
   - Fix force_8bit flag behaviour for DMA mode
   - Move to exec_op interface
   - Use platform_get_irq() to get the interrupt
 * Renesas:
   - Add new NAND controller driver with its bindings and MAINTAINERS entry
 * Onenand:
   - Remove redundant variable ooblen
 * MPC5121:
   - Remove unused variable in ads5121_select_chip()
 * GPMI:
   - Add ERR007117 protection for nfc_apply_timings
   - Remove explicit default gpmi clock setting for i.MX6
   - Use platform_get_irq_byname() to get the interrupt
   - Remove unneeded variable
 * Ingenic:
   - JZ4740 needs 'oob_first' read page function
 * Davinci:
   - Rewrite function description
   - Avoid duplicated page read
   - Don't calculate ECC when reading page
 
 SPI NOR core changes:
 * Add Pratyush as SPI NOR co-maintainer.
 * Flash parameters initialization was done in a spaghetti way. Clean
   flash parameters initialization.
 * Rework the flash_info flags and clarify where one should be used.
 * Initialize all flash parameters based on JESD216 SFDP where possible.
   Flash parameters and settings that are SFDP discoverable should not be
   duplicated via flash_info flags at flash declaration.
 * Remove debugfs entries that duplicate sysfs entries.
 
 SPI NOR manufacturer driver changes:
 * Use late_init() hook in various drivers to make it clear that those
   flash parameters are either not declared in the JESD216 SFDP standard,
   or the SFDP tables which define those flash parameters are not defined
   by the flash.
 * Fix mtd size for s3an flashes.
 * Write 2 bytes when disabling Octal DTR mode: 1 byte long transactions are
   not allowed in 8D-8D-8D mode.
 
 Hyperbus changes:
 * Couple of fixes in Renesas hyperbus rpc-if driver to avoid crash on
   module remove and for missing check for error value in probe.
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Merge tag 'mtd/for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux

Pull MTD updates from Miquel Raynal:
 "MTD core changes:

   - mtdchar: Prevent unbounded allocation in MEMWRITE ioctl

   - gen_probe: Use bitmap_zalloc() when applicable

   - Introduce an expert mode for forensics and debugging purposes

   - Clear out unregistered devices a bit more

   - Provide unique name for nvmem device

   - Remove unused header file <linux/mtd/latch-addr-flash.h>

   - Fixed breaking list in __mtd_del_partition.

  MTD device changes:

   - Warn about failure to unregister mtd device in sst25l, mchp48l640,
     mchp23k256, and dataflash drivers.

  Raw NAND core changes:

   - Export nand_read_page_hwecc_oob_first()

  GPMC memory controller for OMAP2 NAND controller changes:

   - Add support for AM64 SoC and allow build on K3 platforms

   - Use a compatible match table when checking for NAND controller

   - Use platform_get_irq() to get the interrupt

  Raw NAND controller changes:

   - OMAP2 NAND controller:
      - Document the missing 'rb-gpios' DT property
      - Drop unused variable
      - Fix force_8bit flag behaviour for DMA mode
      - Move to exec_op interface
      - Use platform_get_irq() to get the interrupt

   - Renesas:
      - Add new NAND controller driver with its bindings and MAINTAINERS entry

   - Onenand:
      - Remove redundant variable ooblen

   - MPC5121:
      - Remove unused variable in ads5121_select_chip()

   - GPMI:
      - Add ERR007117 protection for nfc_apply_timings
      - Remove explicit default gpmi clock setting for i.MX6
      - Use platform_get_irq_byname() to get the interrupt
      - Remove unneeded variable

   - Ingenic:
      - JZ4740 needs 'oob_first' read page function

   - Davinci:
      - Rewrite function description
      - Avoid duplicated page read
      - Don't calculate ECC when reading page

  SPI NOR core changes:

   - Add Pratyush as SPI NOR co-maintainer.

   - Flash parameters initialization was done in a spaghetti way. Clean
     flash parameters initialization.

   - Rework the flash_info flags and clarify where one should be used.

   - Initialize all flash parameters based on JESD216 SFDP where
     possible. Flash parameters and settings that are SFDP discoverable
     should not be duplicated via flash_info flags at flash declaration.

   - Remove debugfs entries that duplicate sysfs entries.

  SPI NOR manufacturer driver changes:

   - Use late_init() hook in various drivers to make it clear that those
     flash parameters are either not declared in the JESD216 SFDP
     standard, or the SFDP tables which define those flash parameters
     are not defined by the flash.

   - Fix mtd size for s3an flashes.

   - Write 2 bytes when disabling Octal DTR mode: 1 byte long
     transactions are not allowed in 8D-8D-8D mode.

  Hyperbus changes:

   - Couple of fixes in Renesas hyperbus rpc-if driver to avoid crash on
     module remove and for missing check for error value in probe"

* tag 'mtd/for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (71 commits)
  mtd: spi-nor: Remove debugfs entries that duplicate sysfs entries
  mtd: spi-nor: micron-st: write 2 bytes when disabling Octal DTR mode
  mtd: spi-nor: spansion: write 2 bytes when disabling Octal DTR mode
  mtd: spi-nor: core: use 2 data bytes for template ops
  mtd: spi-nor: Constify part specific fixup hooks
  mtd: spi-nor: core: Remove reference to spi-nor.c
  mtd: rawnand: gpmi: Use platform_get_irq_byname() to get the interrupt
  mtd: rawnand: omap_elm: Use platform_get_irq() to get the interrupt
  mtd: rawnand: omap2: Select GPMC device driver for ARCH_K3
  memory: omap-gpmc: Use a compatible match table when checking for NAND controller
  memory: omap-gpmc: Add support for GPMC on AM64 SoC
  dt-bindings: memory-controllers: ti,gpmc: Add compatible for AM64
  memory: omap-gpmc: Use platform_get_irq() to get the interrupt
  MAINTAINERS: Add an entry for Renesas NAND controller
  mtd: rawnand: renesas: Add new NAND controller driver
  dt-bindings: mtd: renesas: Describe Renesas R-Car Gen3 & RZ/N1 NAND controller
  mtd: rawnand: gpmi: remove unneeded variable
  mtd: rawnand: omap2: drop unused variable
  mtd: rawnand: omap2: fix force_8bit flag behaviour for DMA mode
  mtd: rawnand: omap2: Add compatible for AM64 SoC
  ...
2022-01-11 11:35:28 -08:00
George G. Davis
baaf965f94 mtd: hyperbus: rpc-if: fix bug in rpcif_hb_remove
The following KASAN BUG is observed when testing the rpc-if driver on
rcar-gen3:

root@rcar-gen3:~# modprobe -r rpc-if
[  101.930146] ==================================================================
[  101.937408] BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x518/0x25d0
[  101.944240] Read of size 8 at addr ffff0004c5be2750 by task modprobe/664
[  101.950959]
[  101.952466] CPU: 2 PID: 664 Comm: modprobe Not tainted 5.14.0-rc1-00342-g1a1464d7aa31 #1
[  101.960578] Hardware name: Renesas H3ULCB board based on r8a77951 (DT)
[  101.967120] Call trace:
[  101.969580]  dump_backtrace+0x0/0x2c0
[  101.973275]  show_stack+0x1c/0x30
[  101.976616]  dump_stack_lvl+0x9c/0xd8
[  101.980301]  print_address_description.constprop.0+0x74/0x2b8
[  101.986071]  kasan_report+0x1f4/0x26c
[  101.989757]  __asan_load8+0x98/0xd4
[  101.993266]  __lock_acquire+0x518/0x25d0
[  101.997215]  lock_acquire.part.0+0x18c/0x360
[  102.001506]  lock_acquire+0x74/0x90
[  102.005013]  _raw_spin_lock_irq+0x98/0x130
[  102.009131]  __pm_runtime_disable+0x30/0x210
[  102.013427]  rpcif_hb_remove+0x5c/0x70 [rpc_if]
[  102.018001]  platform_remove+0x40/0x80
[  102.021771]  __device_release_driver+0x234/0x350
[  102.026412]  driver_detach+0x158/0x20c
[  102.030179]  bus_remove_driver+0xa0/0x140
[  102.034212]  driver_unregister+0x48/0x80
[  102.038153]  platform_driver_unregister+0x18/0x24
[  102.042879]  rpcif_platform_driver_exit+0x1c/0x34 [rpc_if]
[  102.048400]  __arm64_sys_delete_module+0x210/0x310
[  102.053212]  invoke_syscall+0x60/0x190
[  102.056986]  el0_svc_common+0x12c/0x144
[  102.060844]  do_el0_svc+0x88/0xac
[  102.064181]  el0_svc+0x24/0x3c
[  102.067257]  el0t_64_sync_handler+0x1a8/0x1b0
[  102.071634]  el0t_64_sync+0x198/0x19c
[  102.075315]
[  102.076815] Allocated by task 628:
[  102.080781]
[  102.082280] Last potentially related work creation:
[  102.087524]
[  102.089022] The buggy address belongs to the object at ffff0004c5be2000
[  102.089022]  which belongs to the cache kmalloc-2k of size 2048
[  102.101555] The buggy address is located 1872 bytes inside of
[  102.101555]  2048-byte region [ffff0004c5be2000, ffff0004c5be2800)
[  102.113486] The buggy address belongs to the page:
[  102.118409]
[  102.119908] Memory state around the buggy address:
[  102.124711]  ffff0004c5be2600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  102.131947]  ffff0004c5be2680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  102.139181] >ffff0004c5be2700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  102.146412]                                                  ^
[  102.152257]  ffff0004c5be2780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  102.159491]  ffff0004c5be2800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  102.166723] ==================================================================

The above bug is caused by use of the wrong pointer in the
rpcif_disable_rpm() call. Fix the bug by using the correct pointer.

Fixes: 5de15b610f ("mtd: hyperbus: add Renesas RPC-IF driver")
Signed-off-by: George G. Davis <davis.george@siemens.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210716204935.25859-1-george_davis@mentor.com
2021-11-21 17:21:40 +05:30
Lad Prabhakar
b04cc0d912 memory: renesas-rpc-if: Add support for RZ/G2L
SPI Multi I/O Bus Controller on RZ/G2L SoC is almost identical to
the RPC-IF interface found on R-Car Gen3 SoC's.

This patch adds a new compatible string for the RZ/G2L family so
that the timing values on RZ/G2L can be adjusted.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20211025205631.21151-8-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
2021-11-16 12:09:11 +01:00
Lad Prabhakar
981387ed06 mtd: hyperbus: rpc-if: Check return value of rpcif_sw_init()
rpcif_sw_init() can fail so make sure we check the return value
of it and on error exit rpcif_hb_probe() callback with error code.

Fixes: 5de15b610f ("mtd: hyperbus: add Renesas RPC-IF driver")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211025205631.21151-5-prabhakar.mahadev-lad.rj@bp.renesas.com
2021-11-15 11:49:29 +05:30
Vignesh Raghavendra
6402f4ce95 mtd: hyperbus: Fix build failure when only RPCIF_HYPERBUS is enabled
commit 5de15b610f ("mtd: hyperbus: add Renesas RPC-IF driver") leads
to build failure[1] with COMPILE_TEST and RPCIF_HYPERBUS enabled. This
is because driver needs functions RENESAS_RPCIF which is only buildable
for CONFIG_ARCH_RENESAS.

Fix this by dropping COMPILE_TEST from RPCIF_HYPERBUS Kconfig entry.
This ensures driver can be built only when RENESAS_RPCIF is also
selected.

[1]:
rpc-if.c:(.text+0x20): undefined reference to `rpcif_disable_rpm' ld:
drivers/mtd/hyperbus/rpc-if.o: in function `rpcif_hb_prepare_read':
rpc-if.c:(.text+0xd6): undefined reference to `rpcif_prepare' ld:
drivers/mtd/hyperbus/rpc-if.o: in function `rpcif_hb_read16':
[...]

Fixes: 5de15b610f ("mtd: hyperbus: add Renesas RPC-IF driver") leads
Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-12 21:12:08 +02:00
Sergei Shtylyov
5de15b610f mtd: hyperbus: add Renesas RPC-IF driver
Add the HyperFLash driver for the Renesas RPC-IF.  It's the "front end"
driver using the "back end" APIs in the main driver to talk to the real
hardware.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/78abb851-2beb-fe7d-87e5-ce58ee877d35@gmail.com
2020-10-06 12:36:21 +05:30
Vignesh Raghavendra
00c9cf49a6 mtd: hyperbus: hbmc-am654: Add DMA support for reads
AM654 HyperBus controller provides MMIO interface to read data from
flash. So add DMA memcpy support for reading data over MMIO interface.
This provides 5x improvement in throughput and reduces CPU usage as
well.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200924081214.16934-5-vigneshr@ti.com
2020-09-30 13:35:18 +05:30
Vignesh Raghavendra
992df3bb35 mtd: hyperbus: hbmc-am654: Drop pm_runtime* calls from probe
Recent genpd changes for K3 platform ensure device is ON before driver
probe is called. Therefore, drop redundant pm_runtime_* calls from
driver to simplify the code.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200924081214.16934-4-vigneshr@ti.com
2020-09-30 13:35:18 +05:30
Vignesh Raghavendra
aca31ce968 mtd: hyperbus: hbmc-am654: Fix direct mapping setup flash access
Setting up of direct mapping should be done with flash node's IO
address space and not with controller's IO region.

Fixes: b6fe8bc67d ("mtd: hyperbus: move direct mapping setup to AM654 HBMC driver")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200924081214.16934-3-vigneshr@ti.com
2020-09-30 13:35:18 +05:30
Alexander A. Klimov
614a895fc6 mtd: hyperbus: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-08-02 22:17:05 +02:00
Sergei Shtylyov
b6fe8bc67d mtd: hyperbus: move direct mapping setup to AM654 HBMC driver
The Hyperbus core expects that HyperFlash is always directly mapped for
both read and write, but in reality this may not always be the case, e.g.
Renesas RPC-IF has read only direct mapping. Move the code setting up the
direct mapping from the Hyperbus core to thh TI AM554 HBMC driver.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
2020-03-03 10:13:11 +05:30
Dirk Behme
cb6176ef25 mtd: hyperbus: Add proper error message for missing compatible
In case the compatible "cypress,hyperflash" is not given
output a proper error message.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
2020-03-03 10:12:39 +05:30
Randy Dunlap
dc9cfd2692 mtd: hyperbus: fix dependency and build error
lib/devres.c, which implements devm_ioremap_resource(), is only built
when CONFIG_HAS_IOMEM is set/enabled, so MTD_HYPERBUS should depend
on HAS_IOMEM.  Fixes a build error and a Kconfig warning (as seen on
UML builds):

WARNING: unmet direct dependencies detected for MTD_COMPLEX_MAPPINGS
  Depends on [n]: MTD [=m] && HAS_IOMEM [=n]
  Selected by [m]:
  - MTD_HYPERBUS [=m] && MTD [=m]

ERROR: "devm_ioremap_resource" [drivers/mtd/hyperbus/hyperbus-core.ko] undefined!

Fixes: dcc7d3446a ("mtd: Add support for HyperBus memory devices")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-mtd@lists.infradead.org
Acked-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-08-29 14:31:23 +02:00
Jean Delvare
2b372a9685 mtd: hyperbus: Add hardware dependency to AM654 driver
The hbmc-am654 driver is for the TI AM654, which is an ARM64 SoC, so
don't propose this driver on other architectures unless
build-testing.

Fixes: b07079f164 ("mtd: hyperbus: Add driver for TI's HyperBus memory controller")
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-08-03 02:11:52 +02:00
Vignesh Raghavendra
2d75989d2d mtd: hyperbus: Kconfig: Fix HBMC_AM654 dependencies
On x86_64, when CONFIG_OF is not disabled:

WARNING: unmet direct dependencies detected for MUX_MMIO
  Depends on [n]: MULTIPLEXER [=y] && (OF [=n] || COMPILE_TEST [=n])
  Selected by [y]:
  - HBMC_AM654 [=y] && MTD [=y] && MTD_HYPERBUS [=y]

due to
config HBMC_AM654
	tristate "HyperBus controller driver for AM65x SoC"
	select MULTIPLEXER
	select MUX_MMIO

Fix this by making HBMC_AM654 imply MUX_MMIO instead of select so
that dependencies are taken care of. MUX_MMIO is optional for
functioning of driver.

Fixes: b07079f164 ("mtd: hyperbus: Add driver for TI's HyperBus memory controller")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-08-03 02:11:41 +02:00
Vignesh Raghavendra
b07079f164 mtd: hyperbus: Add driver for TI's HyperBus memory controller
Add driver for HyperBus memory controller on TI's AM654 SoC. Programming
IP is pretty simple and provides direct memory mapped access to
connected Flash devices.

Add basic support for the IP without DMA. Second chip-select is not
supported for now.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-06-28 09:35:45 +02:00
Vignesh Raghavendra
dcc7d3446a mtd: Add support for HyperBus memory devices
Cypress' HyperBus is Low Signal Count, High Performance Double Data Rate
Bus interface between a host system master and one or more slave
interfaces. HyperBus is used to connect microprocessor, microcontroller,
or ASIC devices with random access NOR flash memory (called HyperFlash)
or self refresh DRAM (called HyperRAM).

Its a 8-bit data bus (DQ[7:0]) with  Read-Write Data Strobe (RWDS)
signal and either Single-ended clock(3.0V parts) or Differential clock
(1.8V parts). It uses ChipSelect lines to select b/w multiple slaves.
At bus level, it follows a separate protocol described in HyperBus
specification[1].

HyperFlash follows CFI AMD/Fujitsu Extended Command Set (0x0002) similar
to that of existing parallel NORs. Since HyperBus is x8 DDR bus,
its equivalent to x16 parallel NOR flash with respect to bits per clock
cycle. But HyperBus operates at >166MHz frequencies.
HyperRAM provides direct random read/write access to flash memory
array.

But, HyperBus memory controllers seem to abstract implementation details
and expose a simple MMIO interface to access connected flash.

Add support for registering HyperFlash devices with MTD framework. MTD
maps framework along with CFI chip support framework are used to support
communicating with flash.

Framework is modelled along the lines of spi-nor framework. HyperBus
memory controller (HBMC) drivers calls hyperbus_register_device() to
register a single HyperFlash device. HyperFlash core parses MMIO access
information from DT, sets up the map_info struct, probes CFI flash and
registers it with MTD framework.

Some HBMC masters need calibration/training sequence[3] to be carried
out, in order for DLL inside the controller to lock, by reading a known
string/pattern. This is done by repeatedly reading CFI Query
Identification String. Calibration needs to be done before trying to detect
flash as part of CFI flash probe.

HyperRAM is not supported at the moment.

HyperBus specification can be found at[1]
HyperFlash datasheet can be found at[2]

[1] https://www.cypress.com/file/213356/download
[2] https://www.cypress.com/file/213346/download
[3] http://www.ti.com/lit/ug/spruid7b/spruid7b.pdf
    Table 12-5741. HyperFlash Access Sequence

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-06-27 19:47:58 +02:00