gpu: nvgpu: Implement ELPG flush for gm20b

ELPG flush is initiated from a common broadcast register, but must be
waited on via per-L2 registers. Split gk20a and gm20b versions of
the flush.

Change-Id: I75c2d65e8da311b50d35bee70308b60464ec2d4d
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/401545
Reviewed-by: Automatic_Commit_Validation_User

2 files changed, 63 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/gm20b/hw_ltc_gm20b.h b/drivers/gpu/nvgpu/gm20b/hw_ltc_gm20b.h
index 28c58f50..9840805d 100644
--- a/drivers/gpu/nvgpu/gm20b/hw_ltc_gm20b.h
+++ b/drivers/gpu/nvgpu/gm20b/hw_ltc_gm20b.h
@@ -96,11 +96,11 @@ static inline u32 ltc_ltcs_ltss_cbc_ctrl1_r(void)
 }
 static inline u32 ltc_ltcs_ltss_cbc_ctrl1_clean_active_f(void)
 {
-        return 0x1;
+        return 0x1;
 }
 static inline u32 ltc_ltcs_ltss_cbc_ctrl1_invalidate_active_f(void)
 {
-        return 0x2;
+        return 0x2;
 }
 static inline u32 ltc_ltcs_ltss_cbc_ctrl1_clear_v(u32 r)
 {
@@ -258,6 +258,22 @@ static inline u32 ltc_ltc0_ltss_g_elpg_flush_pending_f(void)
 {
         return 0x1;
 }
+static inline u32 ltc_ltc1_ltss_g_elpg_r(void)
+{
+        return 0x00142214;
+}
+static inline u32 ltc_ltc1_ltss_g_elpg_flush_v(u32 r)
+{
+        return (r >> 0) & 0x1;
+}
+static inline u32 ltc_ltc1_ltss_g_elpg_flush_pending_v(void)
+{
+        return 0x00000001;
+}
+static inline u32 ltc_ltc1_ltss_g_elpg_flush_pending_f(void)
+{
+        return 0x1;
+}
 static inline u32 ltc_ltc0_ltss_intr_r(void)
 {
         return 0x0014020c;
diff --git a/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c b/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
index 5da21c64..43c90970 100644
--- a/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/ltc_gm20b.c
@@ -193,6 +193,50 @@ void gm20b_ltc_isr(struct gk20a *g)
         gk20a_writel(g, ltc_ltc0_ltss_intr_r(), intr);
 }
 
+static void gm20b_ltc_g_elpg_flush_locked(struct gk20a *g)
+{
+        u32 data;
+        bool done[g->ltc_count];
+        s32 retry = 100;
+        int i;
+        int num_done = 0;
+        u32 ltc_d = ltc_ltc1_ltss_g_elpg_r() - ltc_ltc0_ltss_g_elpg_r();
+
+        gk20a_dbg_fn("");
+
+        for (i = 0; i < g->ltc_count; i++)
+                done[i] = 0;
+
+        gk20a_writel(g, ltc_ltcs_ltss_g_elpg_r(),
+                     ltc_ltcs_ltss_g_elpg_flush_pending_f());
+        do {
+                for (i = 0; i < g->ltc_count; i++) {
+                        if (done[i])
+                                continue;
+
+                        data = gk20a_readl(g,
+                                        ltc_ltc0_ltss_g_elpg_r() + ltc_d * i);
+
+                        if (ltc_ltc0_ltss_g_elpg_flush_v(data)) {
+                                gk20a_dbg_info("g_elpg_flush 0x%x", data);
+                        } else {
+                                done[i] = 1;
+                                num_done++;
+                        }
+                }
+
+                if (num_done < g->ltc_count) {
+                        retry--;
+                        usleep_range(20, 40);
+                } else
+                        break;
+        } while (retry >= 0 || !tegra_platform_is_silicon());
+
+        if (retry < 0)
+                gk20a_warn(dev_from_gk20a(g),
+                            "g_elpg_flush too many retries");
+}
+
 void gm20b_init_ltc(struct gpu_ops *gops)
 {
         /* Gk20a reused ops. */
@@ -209,6 +253,6 @@ void gm20b_init_ltc(struct gpu_ops *gops)
         gops->ltc.init_fs_state = gm20b_ltc_init_fs_state;
         gops->ltc.init_comptags = gm20b_ltc_init_comptags;
         gops->ltc.cbc_ctrl = gm20b_ltc_cbc_ctrl;
-        gops->ltc.elpg_flush = gk20a_mm_g_elpg_flush_locked;
+        gops->ltc.elpg_flush = gm20b_ltc_g_elpg_flush_locked;
         gops->ltc.isr = gm20b_ltc_isr;
 }