Commit graph

3 commits

Author SHA1 Message Date
Gustavo A. R. Silva
683313993d mtd: physmap: physmap-bt1-rom: Fix unintentional stack access
Cast &data to (char *) in order to avoid unintentionally accessing
the stack.

Notice that data is of type u32, so any increment to &data
will be in the order of 4-byte chunks, and this piece of code
is actually intended to be a byte offset.

Fixes: b3e79e7682 ("mtd: physmap: Add Baikal-T1 physically mapped ROM support")
Addresses-Coverity-ID: 1497765 ("Out-of-bounds access")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210212104022.GA242669@embeddedor
2021-03-11 09:37:48 +01:00
Serge Semin
18b9c94037 mtd: physmap: physmap-bt1-rom: Fix __iomem addrspace removal warning
sparse is unhappy with us casting the __iomem address space pointer to
a type with no address space attribute specified:

"sparse warnings: (new ones prefixed by >>)"
>> drivers/mtd/maps/physmap-bt1-rom.c:78:18: sparse: sparse: cast removes address space '__iomem' of expression

Indeed we perform the __iomem-less type casting but to an integer
variable. The integer variable isn't dereferenced then, so the casting is
safe and won't cause any problem. But in order to make sparse happy and
keep the code coherent let's fix the warning by converting the local
"shift" and "chunk" variables to the "unsigned int" type (since their
value won't ever exceed three) and cast the __iomem-pointers to uintptr_t.
Add the same fix to the bt1_rom_map_read() method for unification.

Fixes: b3e79e7682 ("mtd: physmap: Add Baikal-T1 physically mapped ROM support")
Link: https://lore.kernel.org/lkml/202011021254.XC70BaQT-lkp@intel.com/
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201125072640.23516-1-Sergey.Semin@baikalelectronics.ru
2020-12-07 12:14:35 +01:00
Serge Semin
b3e79e7682 mtd: physmap: Add Baikal-T1 physically mapped ROM support
Baikal-T1 Boot Controller provides an access to a RO storages, which are
physically mapped into the SoC MMIO space. In particularly there are
Internal ROM embedded into the SoC with a pre-installed firmware,
externally attached SPI flash (also accessed in the read-only mode) and a
memory region, which mirrors one of them in accordance with the currently
enabled system boot mode (also called Boot ROM).

This commit adds the Internal ROM support to the physmap driver of the MTD
kernel subsystem. The driver will create the Internal ROM MTD as long as
it is defined in the system dts file. The physically mapped SPI flash
region will be used to implement the SPI-mem interface. The mirroring
memory region won't be accessible directly since it's redundant due to
both bootable regions being exposed anyway.

Note we had to create a dedicated code for the ROMs since read from the
corresponding memory regions must be done via the dword-aligned addresses.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: linux-mips@vger.kernel.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200920111445.21816-1-Sergey.Semin@baikalelectronics.ru
2020-10-02 09:08:22 +02:00