The aspeed-smc can have multiple SPI devices attached to it in the
device tree. If one of the devices is missing or failing the entire
probe will fail and all MTD devices under the controller will be
removed. On OpenBMC this results in a kernel panic due to missing
rootfs:
[ 0.538774] aspeed-smc 1e620000.spi: Using 50 MHz SPI frequency
[ 0.540471] aspeed-smc 1e620000.spi: w25q01jv-iq (131072 Kbytes)
[ 0.540750] aspeed-smc 1e620000.spi: CE0 window [ 0x20000000 - 0x28000000 ] 128MB
[ 0.540943] aspeed-smc 1e620000.spi: CE1 window [ 0x28000000 - 0x2c000000 ] 64MB
[ 0.541143] aspeed-smc 1e620000.spi: read control register: 203b0041
[ 0.581442] 5 fixed-partitions partitions found on MTD device bmc
[ 0.581625] Creating 5 MTD partitions on "bmc":
[ 0.581854] 0x000000000000-0x0000000e0000 : "u-boot"
[ 0.584472] 0x0000000e0000-0x000000100000 : "u-boot-env"
[ 0.586468] 0x000000100000-0x000000a00000 : "kernel"
[ 0.588465] 0x000000a00000-0x000006000000 : "rofs"
[ 0.590552] 0x000006000000-0x000008000000 : "rwfs"
[ 0.592605] aspeed-smc 1e620000.spi: Using 50 MHz SPI frequency
[ 0.592801] aspeed-smc 1e620000.spi: unrecognized JEDEC id bytes: 00 00 00 00 00 00
[ 0.593039] Deleting MTD partitions on "bmc":
[ 0.593175] Deleting u-boot MTD partition
[ 0.637929] Deleting u-boot-env MTD partition
[ 0.829527] Deleting kernel MTD partition
[ 0.856902] Freeing initrd memory: 1032K
[ 0.866428] Deleting rofs MTD partition
[ 0.906264] Deleting rwfs MTD partition
[ 0.986628] aspeed-smc 1e620000.spi: Aspeed SMC probe failed -2
[ 0.986929] aspeed-smc: probe of 1e620000.spi failed with error -2
...
[ 2.936719] /dev/mtdblock: Can't open blockdev
mount: mounting /dev/mtdblock on run/initramfs/ro failed: No such file or directory
[ 2.963030] MTD: Couldn't look up '/dev/mtdblock': -2
mount: mounting /dev/mtdblock on run/initramfs/rw failed: No such file or directory
Mounting read-write /dev/mtdblock filesystem failed. Please fix and run
mount /dev/mtdblock run/initramfs/rw -t jffs2 -o rw
or perform a factory reset with the clean-rwfs-filesystem option.
Fatal error, triggering kernel panic!
[ 3.013047] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000100
Many BMC designs have two flash chips so that they can handle a hardware
failure of one of them. If one chip failed, it doesn't do any good to
have redundancy if they all get removed anyhow.
Improve the resilience of the probe function to handle one of the
children being missing or failed. Only in the case where all children
fail to probe should the controller be failed out.
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20211229143334.297305-1-patrick@stwcx.xyz
The correct terminology is serial NOR flash or SPI NOR.
s/SPI-NOR/SPI NOR and s/spi-nor/SPI NOR across the subsystem.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Use Joe Perches cvt_fallthrough.pl script to convert
/* fallthrough */
comments (and its derivatives) into a
fallthrough;
statement. This automatically drops useless ones.
Do it MTD-wide.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/linux-mtd/20200325212115.14170-1-miquel.raynal@bootlin.com
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Move all SPI NOR controller drivers to a controllers/ sub-directory
so that we only have SPI NOR related source files under
drivers/mtd/spi-nor/.
Rename spi-nor.c into core.c, we are about to split this file in multiple
source files (one per manufacturer, plus one for the SFDP parsing logic).
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
