From: Shuicheng Lin <shuicheng.lin@xxxxxxxxx> [ Upstream commit 69418db678567bdf9a4992c83d448da462ffa78c ] In some cases, when the driver attempts to read an MMIO register, the hardware may return 0xFFFFFFFF. The current force wake path code treats this as a valid response, as it only checks the BIT. However, 0xFFFFFFFF should be considered an invalid value, indicating a potential issue. To address this, we should add a log entry to highlight this condition and return failure. The force wake failure log level is changed from notice to err to match the failure return value. v2 (Matt Brost): - set ret value (-EIO) to kick the error to upper layers v3 (Rodrigo): - add commit message for the log level promotion from notice to err v4: - update reviewed info Suggested-by: Alex Zuo <alex.zuo@xxxxxxxxx> Signed-off-by: Shuicheng Lin <shuicheng.lin@xxxxxxxxx> Cc: Matthew Brost <matthew.brost@xxxxxxxxx> Cc: Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx> Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@xxxxxxxxx> Acked-by: Badal Nilawar <badal.nilawar@xxxxxxxxx> Cc: Anshuman Gupta <anshuman.gupta@xxxxxxxxx> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20241017221547.1564029-1-shuicheng.lin@xxxxxxxxx Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> (cherry picked from commit a9fbeabe7226a3bf90f82d0e28a02c18e3c67447) Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/xe/xe_force_wake.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_force_wake.c b/drivers/gpu/drm/xe/xe_force_wake.c index b263fff152737..7d9fc489dcb81 100644 --- a/drivers/gpu/drm/xe/xe_force_wake.c +++ b/drivers/gpu/drm/xe/xe_force_wake.c @@ -115,9 +115,15 @@ static int __domain_wait(struct xe_gt *gt, struct xe_force_wake_domain *domain, XE_FORCE_WAKE_ACK_TIMEOUT_MS * USEC_PER_MSEC, &value, true); if (ret) - xe_gt_notice(gt, "Force wake domain %d failed to ack %s (%pe) reg[%#x] = %#x\n", - domain->id, str_wake_sleep(wake), ERR_PTR(ret), - domain->reg_ack.addr, value); + xe_gt_err(gt, "Force wake domain %d failed to ack %s (%pe) reg[%#x] = %#x\n", + domain->id, str_wake_sleep(wake), ERR_PTR(ret), + domain->reg_ack.addr, value); + if (value == ~0) { + xe_gt_err(gt, + "Force wake domain %d: %s. MMIO unreliable (forcewake register returns 0xFFFFFFFF)!\n", + domain->id, str_wake_sleep(wake)); + ret = -EIO; + } return ret; } -- 2.43.0
