video: tegra: host: Disable 3d powergating

It is possible for the 3d block to generate an invalid memory
request during the power up sequence in some cases.  Workaround
is to disable 3d block power gating.

Change-Id: I10efad1f7d3dada7cd3fe18e268f06d60bdbab67
Signed-off-by: Colin Cross <ccross@android.com>

diff --git a/drivers/video/tegra/host/nvhost_acm.c b/drivers/video/tegra/host/nvhost_acm.c
index c4ac035a26ec8faca1ef3b8ca4a3d30f6ea22f00..a4bbce2b6f1ddec778c677877644e0579fb93bbe 100644 (file)
--- a/drivers/video/tegra/host/nvhost_acm.c
+++ b/drivers/video/tegra/host/nvhost_acm.c
@@ -30,6 +30,8 @@
 
 #define ACM_TIMEOUT 1*HZ
 
+#define DISABLE_3D_POWERGATING
+
 void nvhost_module_busy(struct nvhost_module *mod)
 {
        mutex_lock(&mod->lock);
@@ -139,6 +141,21 @@ int nvhost_module_init(struct nvhost_module *mod, const char *name,
        mod->parent = parent;
        mod->powered = false;
        mod->powergate_id = get_module_powergate_id(name);
+
+#ifdef DISABLE_3D_POWERGATING
+       /*
+        * It is possible for the 3d block to generate an invalid memory
+        * request during the power up sequence in some cases.  Workaround
+        * is to disable 3d block power gating.
+        */
+       if (mod->powergate_id == TEGRA_POWERGATE_3D) {
+               tegra_powergate_sequence_power_up(mod->powergate_id,
+                       mod->clk[0]);
+               clk_disable(mod->clk[0]);
+               mod->powergate_id = -1;
+       }
+#endif
+
        mutex_init(&mod->lock);
        init_waitqueue_head(&mod->idle);
        INIT_DELAYED_WORK(&mod->powerdown, powerdown_handler);