From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
[Why]
If we time out waiting for PMFW to finish the exit sequence and touch
the DMCUB register the system will hang in a hard locked state.
[How]
Pol forever. This covers the case where things take too long but also
enables for debugging to occur since the cores won't be hardlocked.
Reviewed-by: Sung joon Kim <sungjoon.kim@xxxxxxx>
Acked-by: Rodrigo Siqueira <rodrigo.siqueira@xxxxxxx>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
---
drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c b/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
index 4ce8ac966cc8..7724dcadecba 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
@@ -1214,10 +1214,8 @@ static void dc_dmub_srv_notify_idle(const struct dc *dc, bool allow_idle)
static void dc_dmub_srv_exit_low_power_state(const struct dc *dc)
{
- const uint32_t max_num_polls = 10000;
uint32_t allow_state = 0;
uint32_t commit_state = 0;
- int i;
if (dc->debug.dmcub_emulation)
return;
@@ -1244,17 +1242,13 @@ static void dc_dmub_srv_exit_low_power_state(const struct dc *dc)
udelay(dc->debug.ips2_entry_delay_us);
dc->clk_mgr->funcs->exit_low_power_state(dc->clk_mgr);
- for (i = 0; i < max_num_polls; ++i) {
+ for (;;) {
commit_state = dc->hwss.get_idle_state(dc);
if (commit_state & DMUB_IPS2_COMMIT_MASK)
break;
udelay(1);
-
- if (dc->debug.disable_timeout)
- i--;
}
- ASSERT(i < max_num_polls);
if (!dc_dmub_srv_is_hw_pwr_up(dc->ctx->dmub_srv, true))
ASSERT(0);
@@ -1269,17 +1263,13 @@ static void dc_dmub_srv_exit_low_power_state(const struct dc *dc)
dc_dmub_srv_notify_idle(dc, false);
if (!(allow_state & DMUB_IPS1_ALLOW_MASK)) {
- for (i = 0; i < max_num_polls; ++i) {
+ for (;;) {
commit_state = dc->hwss.get_idle_state(dc);
if (commit_state & DMUB_IPS1_COMMIT_MASK)
break;
udelay(1);
-
- if (dc->debug.disable_timeout)
- i--;
}
- ASSERT(i < max_num_polls);
}
}
--
2.42.0
