+++ /dev/null
-From 12b60ef71cc005ee7290f692169d46a7e78df01a Mon Sep 17 00:00:00 2001
-From: Yukimasa Sugizaki <4298265+Terminus-IMRC@users.noreply.github.com>
-Date: Fri, 20 Mar 2020 19:01:23 +0900
-Subject: [PATCH] drm/v3d: Replace wait_for macros to remove use of
- msleep (#3510)
-
-commit 9daee6141cc9c75b09659b02b1cb9eeb2f5e16cc upstream.
-
-The wait_for macro's for Broadcom V3D driver used msleep, which is
-inappropriate due to its inaccuracy at low values (minimum wait time
-is about 30ms on the Raspberry Pi). This sleep was triggering in
-v3d_clean_caches(), causing us to only be able to dispatch ~33 compute
-jobs per second.
-
-This patch replaces the macro with the one from the Intel i915 version
-which uses usleep_range to provide more accurate waits.
-
-v2: Split from the vc4 patch so that we can confidently apply to
- stable (by anholt)
-
-Signed-off-by: James Hughes <james.hughes@raspberrypi.com>
-Signed-off-by: Eric Anholt <eric@anholt.net>
-Link: https://patchwork.freedesktop.org/patch/msgid/20200217153145.13780-1-james.hughes@raspberrypi.com
-Link: https://github.com/raspberrypi/linux/issues/3460
-Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
-
-Co-authored-by: James Hughes <james.hughes@raspberrypi.com>
----
- drivers/gpu/drm/v3d/v3d_drv.h | 41 ++++++++++++++++++++++++-----------
- 1 file changed, 28 insertions(+), 13 deletions(-)
-
---- a/drivers/gpu/drm/v3d/v3d_drv.h
-+++ b/drivers/gpu/drm/v3d/v3d_drv.h
-@@ -260,27 +260,42 @@ struct v3d_csd_job {
- };
-
- /**
-- * _wait_for - magic (register) wait macro
-+ * __wait_for - magic wait macro
- *
-- * Does the right thing for modeset paths when run under kdgb or similar atomic
-- * contexts. Note that it's important that we check the condition again after
-- * having timed out, since the timeout could be due to preemption or similar and
-- * we've never had a chance to check the condition before the timeout.
-+ * Macro to help avoid open coding check/wait/timeout patterns. Note that it's
-+ * important that we check the condition again after having timed out, since the
-+ * timeout could be due to preemption or similar and we've never had a chance to
-+ * check the condition before the timeout.
- */
--#define wait_for(COND, MS) ({ \
-- unsigned long timeout__ = jiffies + msecs_to_jiffies(MS) + 1; \
-- int ret__ = 0; \
-- while (!(COND)) { \
-- if (time_after(jiffies, timeout__)) { \
-- if (!(COND)) \
-- ret__ = -ETIMEDOUT; \
-+#define __wait_for(OP, COND, US, Wmin, Wmax) ({ \
-+ const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \
-+ long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \
-+ int ret__; \
-+ might_sleep(); \
-+ for (;;) { \
-+ const bool expired__ = ktime_after(ktime_get_raw(), end__); \
-+ OP; \
-+ /* Guarantee COND check prior to timeout */ \
-+ barrier(); \
-+ if (COND) { \
-+ ret__ = 0; \
- break; \
- } \
-- msleep(1); \
-+ if (expired__) { \
-+ ret__ = -ETIMEDOUT; \
-+ break; \
-+ } \
-+ usleep_range(wait__, wait__ * 2); \
-+ if (wait__ < (Wmax)) \
-+ wait__ <<= 1; \
- } \
- ret__; \
- })
-
-+#define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \
-+ (Wmax))
-+#define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000)
-+
- static inline unsigned long nsecs_to_jiffies_timeout(const u64 n)
- {
- /* nsecs_to_jiffies64() does not guard against overflow */
projects / openwrt / staging / luka.git / blobdiff