gpu: gp10b: add gfxp_wfi_timeout sysfs node

Add a sysfs node to allow root user to set PRI_FE_GFXP_WFI_TIMEOUT, for gp10b
only, in units of sysclk cycles. Store the set value in a variable, and write
the set value to register after GPU is un-railgated.

NV_PGRAPH_PRI_FE_GFXP_WFI_TIMEOUT is engine_reset after Bug 1623341.

Change default value to be specified in cycles, rather than time.  This value
is almost the current value in cycles calculated each boot.

Bug 1932782

Change-Id: I0a4207e637cd1413a1be95abe2bcce3adccf76fa
Reviewed-on: https://git-master.nvidia.com/r/1540939
Signed-off-by: Jonathan McCaffrey <jmccaffrey@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1580999
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/sysfs.c b/drivers/gpu/nvgpu/common/linux/sysfs.c
index 7b614023..6897fae8 100644
--- a/drivers/gpu/nvgpu/common/linux/sysfs.c
+++ b/drivers/gpu/nvgpu/common/linux/sysfs.c
@@ -954,6 +954,52 @@ static ssize_t pd_max_batches_read(struct device *dev,
 
 static DEVICE_ATTR(pd_max_batches, ROOTRW, pd_max_batches_read, pd_max_batches_store);
 
+static ssize_t gfxp_wfi_timeout_count_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct gk20a *g = get_gk20a(dev);
+        struct gr_gk20a *gr = &g->gr;
+        unsigned long val = 0;
+        int err = -1;
+
+        if (kstrtoul(buf, 10, &val) < 0)
+                return -EINVAL;
+
+        if (val >= 100*1000*1000) /* 100ms @ 1Ghz */
+                return -EINVAL;
+
+        gr->gfxp_wfi_timeout_count = val;
+
+        if (g->ops.gr.init_preemption_state && g->power_on) {
+                err = gk20a_busy(g);
+                if (err)
+                        return err;
+
+                err = gr_gk20a_elpg_protected_call(g,
+                        g->ops.gr.init_preemption_state(g));
+
+                gk20a_idle(g);
+
+                if (err)
+                        return err;
+        }
+
+        return count;
+}
+
+static ssize_t gfxp_wfi_timeout_count_read(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        struct gk20a *g = get_gk20a(dev);
+        struct gr_gk20a *gr = &g->gr;
+        u32 val = gr->gfxp_wfi_timeout_count;
+
+        return snprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static DEVICE_ATTR(gfxp_wfi_timeout_count, (S_IRWXU|S_IRGRP|S_IROTH),
+                gfxp_wfi_timeout_count_read, gfxp_wfi_timeout_count_store);
+
 
 void nvgpu_remove_sysfs(struct device *dev)
 {
@@ -989,6 +1035,7 @@ void nvgpu_remove_sysfs(struct device *dev)
 
         device_remove_file(dev, &dev_attr_czf_bypass);
         device_remove_file(dev, &dev_attr_pd_max_batches);
+        device_remove_file(dev, &dev_attr_gfxp_wfi_timeout_count);
 
         if (strcmp(dev_name(dev), "gpu.0")) {
                 struct kobject *kobj = &dev->kobj;
@@ -1035,6 +1082,7 @@ int nvgpu_create_sysfs(struct device *dev)
 
         error |= device_create_file(dev, &dev_attr_czf_bypass);
         error |= device_create_file(dev, &dev_attr_pd_max_batches);
+        error |= device_create_file(dev, &dev_attr_gfxp_wfi_timeout_count);
 
         if (strcmp(dev_name(dev), "gpu.0")) {
                 struct kobject *kobj = &dev->kobj;