summaryrefslogtreecommitdiff
path: root/drivers/memory
diff options
context:
space:
mode:
authorDmitry Osipenko <digetx@gmail.com>2021-01-20 02:52:10 +0300
committerKrzysztof Kozlowski <krzk@kernel.org>2021-01-23 02:10:40 +0300
commit6ce84ab6492c8634039267d1d9e89fe41dcd4770 (patch)
tree6b9fc5e2e72345a79e4fa84e113a04413f667fac /drivers/memory
parent380def2d4cf257663de42618e57134afeded32dd (diff)
downloadlinux-6ce84ab6492c8634039267d1d9e89fe41dcd4770.tar.xz
memory: tegra: Check whether reset is already asserted
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>
Diffstat (limited to 'drivers/memory')
-rw-r--r--drivers/memory/tegra/mc.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
index 44064de962c2..a21163ccadc4 100644
--- a/drivers/memory/tegra/mc.c
+++ b/drivers/memory/tegra/mc.c
@@ -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);