1 files changed, 65 insertions, 37 deletions

diff --git a/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c b/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
index 74c56487..b96f0b5c 100644
--- a/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
@@ -113,6 +113,7 @@ int gm20b_ltc_cbc_ctrl(struct gk20a *g, enum gk20a_cbc_op op,
                                 gk20a_readl(g, ltc_ltcs_ltss_cbc_param_r()));
         u32 ltc_stride = nvgpu_get_litter_value(g, GPU_LIT_LTC_STRIDE);
         u32 lts_stride = nvgpu_get_litter_value(g, GPU_LIT_LTS_STRIDE);
+        const u32 max_lines = 16384;
 
         gk20a_dbg_fn("");
 
@@ -121,45 +122,72 @@ int gm20b_ltc_cbc_ctrl(struct gk20a *g, enum gk20a_cbc_op op,
         if (gr->compbit_store.mem.size == 0)
                 return 0;
 
-        nvgpu_mutex_acquire(&g->mm.l2_op_lock);
-
-        if (op == gk20a_cbc_op_clear) {
-                gk20a_writel(g, ltc_ltcs_ltss_cbc_ctrl2_r(),
-                        ltc_ltcs_ltss_cbc_ctrl2_clear_lower_bound_f(min));
-                gk20a_writel(g, ltc_ltcs_ltss_cbc_ctrl3_r(),
-                        ltc_ltcs_ltss_cbc_ctrl3_clear_upper_bound_f(max));
-                hw_op = ltc_ltcs_ltss_cbc_ctrl1_clear_active_f();
-        } else if (op == gk20a_cbc_op_clean) {
-                hw_op = ltc_ltcs_ltss_cbc_ctrl1_clean_active_f();
-        } else if (op == gk20a_cbc_op_invalidate) {
-                hw_op = ltc_ltcs_ltss_cbc_ctrl1_invalidate_active_f();
-        } else {
-                BUG_ON(1);
-        }
-        gk20a_writel(g, ltc_ltcs_ltss_cbc_ctrl1_r(),
-                     gk20a_readl(g, ltc_ltcs_ltss_cbc_ctrl1_r()) | hw_op);
-
-        for (ltc = 0; ltc < g->ltc_count; ltc++) {
-                for (slice = 0; slice < slices_per_ltc; slice++) {
-
-                        ctrl1 = ltc_ltc0_lts0_cbc_ctrl1_r() +
-                                ltc * ltc_stride + slice * lts_stride;
-
-                        nvgpu_timeout_init(g, &timeout, 2000,
-                                           NVGPU_TIMER_RETRY_TIMER);
-                        do {
-                                val = gk20a_readl(g, ctrl1);
-                                if (!(val & hw_op))
-                                        break;
-                                nvgpu_udelay(5);
-                        } while (!nvgpu_timeout_expired(&timeout));
-
-                        if (nvgpu_timeout_peek_expired(&timeout)) {
-                                nvgpu_err(g, "comp tag clear timeout");
-                                err = -EBUSY;
-                                goto out;
+        while (1) {
+                const u32 iter_max = min(min + max_lines - 1, max);
+                bool full_cache_op = true;
+
+                nvgpu_mutex_acquire(&g->mm.l2_op_lock);
+
+                gk20a_dbg_info("clearing CBC lines %u..%u", min, iter_max);
+
+                if (op == gk20a_cbc_op_clear) {
+                        gk20a_writel(
+                                g, ltc_ltcs_ltss_cbc_ctrl2_r(),
+                                ltc_ltcs_ltss_cbc_ctrl2_clear_lower_bound_f(
+                                        min));
+                        gk20a_writel(
+                                g, ltc_ltcs_ltss_cbc_ctrl3_r(),
+                                ltc_ltcs_ltss_cbc_ctrl3_clear_upper_bound_f(
+                                        iter_max));
+                        hw_op = ltc_ltcs_ltss_cbc_ctrl1_clear_active_f();
+                        full_cache_op = false;
+                } else if (op == gk20a_cbc_op_clean) {
+                        /* this is full-cache op */
+                        hw_op = ltc_ltcs_ltss_cbc_ctrl1_clean_active_f();
+                } else if (op == gk20a_cbc_op_invalidate) {
+                        /* this is full-cache op */
+                        hw_op = ltc_ltcs_ltss_cbc_ctrl1_invalidate_active_f();
+                } else {
+                        nvgpu_err(g, "Unknown op: %u", (unsigned)op);
+                        err = -EINVAL;
+                        goto out;
+                }
+                gk20a_writel(g, ltc_ltcs_ltss_cbc_ctrl1_r(),
+                             gk20a_readl(g,
+                                         ltc_ltcs_ltss_cbc_ctrl1_r()) | hw_op);
+
+                for (ltc = 0; ltc < g->ltc_count; ltc++) {
+                        for (slice = 0; slice < slices_per_ltc; slice++) {
+
+                                ctrl1 = ltc_ltc0_lts0_cbc_ctrl1_r() +
+                                        ltc * ltc_stride + slice * lts_stride;
+
+                                nvgpu_timeout_init(g, &timeout, 2000,
+                                                   NVGPU_TIMER_RETRY_TIMER);
+                                do {
+                                        val = gk20a_readl(g, ctrl1);
+                                        if (!(val & hw_op))
+                                                break;
+                                        nvgpu_udelay(5);
+                                } while (!nvgpu_timeout_expired(&timeout));
+
+                                if (nvgpu_timeout_peek_expired(&timeout)) {
+                                        nvgpu_err(g, "comp tag clear timeout");
+                                        err = -EBUSY;
+                                        goto out;
+                                }
                         }
                 }
+
+                /* are we done? */
+                if (full_cache_op || iter_max == max)
+                        break;
+
+                /* note: iter_max is inclusive upper bound */
+                min = iter_max + 1;
+
+                /* give a chance for higher-priority threads to progress */
+                nvgpu_mutex_release(&g->mm.l2_op_lock);
         }
 out:
         trace_gk20a_ltc_cbc_ctrl_done(g->name);