On Wed, 7 Oct 2020 at 01:43, Joel Stanley <j...@jms.id.au> wrote: > > On Wed, 2 Sep 2020 at 09:31, Cédric Le Goater <c...@kaod.org> wrote: > > > > Hello, > > > > JEDEC STANDARD JESD216 for Serial Flash Discovery Parameters (SFDP) > > provides a mean to describe the features of a serial flash device > > using a set of internal parameter tables. Support in Linux has been > > added some time ago and the spi-nor driver is using it more often > > to detect the flash settings and even flash models. > > > > This is the initial framework for the RDSFDP command giving access to > > a private SFDP area under the flash. > > > > The patches available here : > > > > https://github.com/legoater/qemu/commits/aspeed-5.2 > > Reviewed-by: Joel Stanley <j...@jms.id.au> > Tested-by: Joel Stanley <j...@jms.id.au> > > Note that these need to be rebased on master; there are some minor conflicts. > > These patches have proved essential in debugging a recent kernel > regression. Thanks for adding this support Cédric.
For reference, an OpenBMC UBI based NOR image with an upstream (5.8, 5.9-rc) kernel can be used to reproduce the bug as follows: qemu-system-arm -M witherspoon-bmc -nic user -nographic \ -drive file=obmc-phosphor-image-witherspoon.ubi.mtd,format=raw,if=mtd \ -kernel aspeed-g5-dev/arch/arm/boot/zImage \ -dtb aspeed-g5-dev/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dtb \ -append "console=ttyS4,115200n8 ubi.mtd=obmc-ubi,0,0,0 ubi.mtd=alt-obmc-ubi,0,0,4 ro rootfstype=squashfs ubi.block=0,1 root=/dev/ubiblock0_1" The ubi.mtd can be found here[1]. This assumes you're running qemu with this series applied, and an upstream kernel built with aspeed_g5_defconfig: git checkout v5.8 CROSS_COMPILE="ccache arm-linux-gnueabi-" ARCH=arm make -j8 O=aspeed-g5-dev aspeed_g5_defconfig CROSS_COMPILE="ccache arm-linux-gnueabi-" ARCH=arm make -j8 O=aspeed-g5-dev The fix for the Linux kernel issue is on the linux-mtd list[2]. WIthout the fix, the kernel will fail to attach the UBI volume: [ 1.453224] ubi0: default fastmap pool size: 25 [ 1.453370] ubi0: default fastmap WL pool size: 12 [ 1.453505] ubi0: attaching mtd3 [ 1.467316] ubi0 error: ubi_compare_lebs: unsupported on-flash UBI format [ 1.467902] ubi0 error: ubi_attach_mtd_dev: failed to attach mtd3, error -22 With the fix, the system will boot through to userspace. Cheers, Joel [1] https://jenkins.openbmc.org/view/latest/job/latest-master/label=docker-builder,target=witherspoon/lastSuccessfulBuild/artifact/openbmc/build/tmp/deploy/images/witherspoon/obmc-phosphor-image-witherspoon.ubi.mtd [2] https://lore.kernel.org/linux-mtd/cacpk8xcel_qhcqohfus27rei0vwfrjafjfl6jkvw9pwxjj2...@mail.gmail.com/ > > Cheers, > > Joel > > > > > Thanks, > > > > C. > > > > Changes in v2: > > > > - fixed dummy value > > - replaced 'sfdp' table by a 'sfdp_read' handler > > - more SFDP tables > > - fixed Aspeed SMC support > > - introduced mx25l25635f chip model for test under Linux. > > > > Cédric Le Goater (9): > > m25p80: Add basic support for the SFDP command > > m25p80: Add the n25q256a SFDP table > > m25p80: Add the mx25l25635e SFPD table > > m25p80: Add the mx25l25635f SFPD table > > m25p80: Add the mx66l1g45g SFDP table > > m25p80: Add the w25q256 SFPD table > > m25p80: Add the w25q512jv SFPD table > > arm/aspeed: Replace mx25l25635e chip model > > aspeed/smc: Add support for RDSFDP command > > > > hw/block/m25p80_sfdp.h | 27 ++++ > > include/hw/ssi/aspeed_smc.h | 1 + > > hw/arm/aspeed.c | 6 +- > > hw/block/m25p80.c | 47 +++++- > > hw/block/m25p80_sfdp.c | 296 ++++++++++++++++++++++++++++++++++++ > > hw/ssi/aspeed_smc.c | 21 ++- > > MAINTAINERS | 2 +- > > hw/block/meson.build | 1 + > > hw/block/trace-events | 1 + > > 9 files changed, 385 insertions(+), 17 deletions(-) > > create mode 100644 hw/block/m25p80_sfdp.h > > create mode 100644 hw/block/m25p80_sfdp.c > > > > -- > > 2.25.4 > >
