gpu: nvgpu: At FB reset wait for scrubber

We need to wait for scrubber to have finished before we can allow
any accesses to memory. Do the wait in place where on iGPU we would
do FB reset.

Bug 1799537
Bug 1815139

Change-Id: Ic92dee936388a13c4abf0b295fd99581522c430f
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1235541
(cherry picked from commit 1ef73ecb4e37da042e7117426ab2823b7f4528dc)
Reviewed-on: http://git-master/r/1239955
GVS: Gerrit_Virtual_Submit

1 files changed, 20 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gp106/fb_gp106.c b/drivers/gpu/nvgpu/gp106/fb_gp106.c
index 1c5b3e0a..ef9f1094 100644
--- a/drivers/gpu/nvgpu/gp106/fb_gp106.c
+++ b/drivers/gpu/nvgpu/gp106/fb_gp106.c
@@ -12,14 +12,33 @@
  */
 
 #include <linux/types.h>
+#include <linux/delay.h>
 
 #include "gk20a/gk20a.h"
 #include "gp10b/fb_gp10b.h"
+#include "hw_fb_gp106.h"
+
+#define HW_SCRUB_TIMEOUT_DEFAULT        100 /* usec */
+#define HW_SCRUB_TIMEOUT_MAX            2000000 /* usec */
+
+static void gp106_fb_reset(struct gk20a *g)
+{
+        int retries = HW_SCRUB_TIMEOUT_MAX / HW_SCRUB_TIMEOUT_DEFAULT;
+        /* wait for memory to be accessible */
+        do {
+                u32 w = gk20a_readl(g, fb_niso_scrub_status_r());
+                if (fb_niso_scrub_status_flag_v(w)) {
+                        gk20a_dbg_fn("done");
+                        break;
+                }
+                udelay(HW_SCRUB_TIMEOUT_DEFAULT);
+        } while (--retries);
+}
 
 void gp106_init_fb(struct gpu_ops *gops)
 {
         gp10b_init_fb(gops);
 
         gops->fb.init_fs_state = NULL;
-        gops->fb.reset = NULL;
+        gops->fb.reset = gp106_fb_reset;
 }