Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-23 12:42:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

memory: tegra: Check whether reset is already asserted

Browse Source 
Check whether memory client reset is already asserted in order to prevent
DMA-flush error on trying to re-assert an already asserted reset.

This becomes a problem once PMC GENPD is enabled to use memory resets
since GENPD will get a error and fail to toggle power domain. PMC GENPDs
can't be toggled safely without holding memory reset on Tegra and we're
about to fix this.

Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210119235210.13006-1-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
This commit is contained in:
Dmitry Osipenko 2021-01-20 02:52:10 +03:00 committed by Krzysztof Kozlowski
parent 380def2d4c
commit 6ce84ab649
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/memory/tegra/mc.c
View File

@ -176,6 +176,13 @@ static int tegra_mc_hotreset_assert(struct reset_controller_dev *rcdev,
if (!rst_ops)
return -ENODEV;
/* DMA flushing will fail if reset is already asserted */
if (rst_ops->reset_status) {
/* check whether reset is asserted */
if (rst_ops->reset_status(mc, rst))
return 0;
}
if (rst_ops->block_dma) {
/* block clients DMA requests */
err = rst_ops->block_dma(mc, rst);