Accessing registers for an unclocked block is an insta-reboot on snapdragon devices. So add a bit of logic to track the enable_count so we can WARN_ON() unclocked register writes. This makes it much easier to track down mistakes.

Signed-off-by: Rob Clark robdclark@gmail.com --- drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c | 5 +++++ drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h | 4 ++++ 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c index d3d6b4c..1189128 100644 --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c @@ -249,6 +249,9 @@ int mdp5_disable(struct mdp5_kms *mdp5_kms) { DBG("");

+ mdp5_kms->enable_count--; + WARN_ON(mdp5_kms->enable_count < 0); + clk_disable_unprepare(mdp5_kms->ahb_clk); clk_disable_unprepare(mdp5_kms->axi_clk); clk_disable_unprepare(mdp5_kms->core_clk); @@ -262,6 +265,8 @@ int mdp5_enable(struct mdp5_kms *mdp5_kms) { DBG("");

+ mdp5_kms->enable_count++; + clk_prepare_enable(mdp5_kms->ahb_clk); clk_prepare_enable(mdp5_kms->axi_clk); clk_prepare_enable(mdp5_kms->core_clk); diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h index 8bdb7ee..c78faf0 100644 --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h @@ -80,6 +80,8 @@ struct mdp5_kms { bool rpm_enabled;

struct mdp_irq error_handler; + + int enable_count; }; #define to_mdp5_kms(x) container_of(x, struct mdp5_kms, base)

@@ -171,11 +173,13 @@ struct mdp5_encoder {

static inline void mdp5_write(struct mdp5_kms *mdp5_kms, u32 reg, u32 data) { + WARN_ON(mdp5_kms->enable_count <= 0); msm_writel(data, mdp5_kms->mmio + reg); }

static inline u32 mdp5_read(struct mdp5_kms *mdp5_kms, u32 reg) { + WARN_ON(mdp5_kms->enable_count <= 0); return msm_readl(mdp5_kms->mmio + reg); }