From: Rob Clark <robdclark@gmail.com>
Date: Mon, 3 Jul 2017 13:13:57 -0400
Subject: drm/msm/mdp5: add tracking for clk enable-count
Git-commit: a7d3bb0045365ff84be35e3a4715af5d0216b7bd
Patch-mainline: v4.14-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
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>
Acked-by: Petr Tesarik <ptesarik@suse.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(+)
--- 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_k
{
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_km
{
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);
--- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h
+++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h
@@ -76,6 +76,8 @@ 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)
@@ -167,11 +169,13 @@ 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);
}