u-boot/drivers/nvme
Jagan Teki 1a027a90aa nvme: Invalidate dcache before submitting admin cmd
This patch try to avoids eviction of dirty lines during DMA
transfer. The code right now execute the following step:

- allocate the buffer
- start a dma operation using the non-coherent dma buffer
- invalidate cache lines associated with the buffer
- read the buffer

This can lead to reading back not valid information, because the cache
controller could evict dirty cache lines belonging to the buffer *after*
the DMA operation has started to fill the DRAM.
In order to avoid this, a new invalidation is required *before* starting
the DMA operation. The patch just adds an invalidation before submitting
the DMA command.

Example below shows the nvme disk scan result without the following
patch

=> nvme scan
nvme_get_info_from_identify: nn = 544502629, vwc = 100,
sn = dev_0T, mn = `�\�, fr = t_part, mdts = 105

So, invalidating the cache before submitting the admin command,
fix the cpu read.

Cc: André Przywara <andre.przywara@arm.com>
Reported-by: Suniel Mahesh <sunil@amarulasolutions.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Suniel Mahesh <sunil@amarulasolutions.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-06-23 14:43:23 -04:00
..
Kconfig SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
Makefile SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
nvme_show.c nvme: Fix warning of cast from pointer to integer of different size 2019-05-19 16:17:33 +08:00
nvme-uclass.c common: Drop part.h from common header 2020-05-18 17:33:33 -04:00
nvme.c nvme: Invalidate dcache before submitting admin cmd 2020-06-23 14:43:23 -04:00
nvme.h nvme: add accessor to namespace id and eui64 2019-10-06 16:02:37 +02:00