drm/i915/sbi: add a dedicated mutex for LPT/WPT IOSF sideband

The LPT/WPT IOSF sideband is unrelated to pcode or VLV/CHV IOSF
sideband. It's just confusing to piggyback on the same mutex. Add a
dedicated lock with init and cleanup functions.

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/139933094fe51fccdbe14d4e20df69782e801905.1730193891.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index b3eb35fa5ff8e2f919ad28b30db97824553ee481..a777532db98e343f0eaf985eb6f5193f888577c5 100644 (file)
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -104,6 +104,7 @@
 #include "intel_pci_config.h"
 #include "intel_pcode.h"
 #include "intel_region_ttm.h"
+#include "intel_sbi.h"
 #include "vlv_suspend.h"
 
 static const struct drm_driver i915_drm_driver;
@@ -231,6 +232,7 @@ static int i915_driver_early_probe(struct drm_i915_private *dev_priv)
        spin_lock_init(&dev_priv->irq_lock);
        spin_lock_init(&dev_priv->gpu_error.lock);
 
+       intel_sbi_init(dev_priv);
        mutex_init(&dev_priv->sb_lock);
        cpu_latency_qos_add_request(&dev_priv->sb_qos, PM_QOS_DEFAULT_VALUE);
 
@@ -292,6 +294,7 @@ static void i915_driver_late_release(struct drm_i915_private *dev_priv)
 
        cpu_latency_qos_remove_request(&dev_priv->sb_qos);
        mutex_destroy(&dev_priv->sb_lock);
+       intel_sbi_fini(dev_priv);
 
        i915_params_free(&dev_priv->params);
 }

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index fe2c251a44368a2979edb4970adcf51b7672044e..64a8591ae3e04fe09ea8adebfdc05572e1ec93c2 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -236,6 +236,9 @@ struct drm_i915_private {
        spinlock_t irq_lock;
        bool irqs_enabled;
 
+       /* LPT/WPT IOSF sideband protection */
+       struct mutex sbi_lock;
+
        /* Sideband mailbox protection */
        struct mutex sb_lock;
        struct pm_qos_request sb_qos;

diff --git a/drivers/gpu/drm/i915/intel_sbi.c b/drivers/gpu/drm/i915/intel_sbi.c
index 862b5b9992eb8ad745116ae6c385279d008bdd47..41e85ac773dce3392fb52534ff9cf60d5642cc76 100644 (file)
--- a/drivers/gpu/drm/i915/intel_sbi.c
+++ b/drivers/gpu/drm/i915/intel_sbi.c
@@ -17,7 +17,7 @@ static int intel_sbi_rw(struct drm_i915_private *i915, u16 reg,
        struct intel_uncore *uncore = &i915->uncore;
        u32 cmd;
 
-       lockdep_assert_held(&i915->sb_lock);
+       lockdep_assert_held(&i915->sbi_lock);
 
        if (intel_wait_for_register_fw(uncore,
                                       SBI_CTL_STAT, SBI_BUSY, 0,
@@ -59,12 +59,12 @@ static int intel_sbi_rw(struct drm_i915_private *i915, u16 reg,
 
 void intel_sbi_lock(struct drm_i915_private *i915)
 {
-       mutex_lock(&i915->sb_lock);
+       mutex_lock(&i915->sbi_lock);
 }
 
 void intel_sbi_unlock(struct drm_i915_private *i915)
 {
-       mutex_unlock(&i915->sb_lock);
+       mutex_unlock(&i915->sbi_lock);
 }
 
 u32 intel_sbi_read(struct drm_i915_private *i915, u16 reg,
@@ -82,3 +82,13 @@ void intel_sbi_write(struct drm_i915_private *i915, u16 reg, u32 value,
 {
        intel_sbi_rw(i915, reg, destination, &value, false);
 }
+
+void intel_sbi_init(struct drm_i915_private *i915)
+{
+       mutex_init(&i915->sbi_lock);
+}
+
+void intel_sbi_fini(struct drm_i915_private *i915)
+{
+       mutex_destroy(&i915->sbi_lock);
+}

diff --git a/drivers/gpu/drm/i915/intel_sbi.h b/drivers/gpu/drm/i915/intel_sbi.h
index f91bd03aa82643b39ebb963226a0c2f1a5b1d38b..85161a4f13b8aa9f9901d49a6bab5e3662afca74 100644 (file)
--- a/drivers/gpu/drm/i915/intel_sbi.h
+++ b/drivers/gpu/drm/i915/intel_sbi.h
@@ -15,6 +15,8 @@ enum intel_sbi_destination {
        SBI_MPHY,
 };
 
+void intel_sbi_init(struct drm_i915_private *i915);
+void intel_sbi_fini(struct drm_i915_private *i915);
 void intel_sbi_lock(struct drm_i915_private *i915);
 void intel_sbi_unlock(struct drm_i915_private *i915);
 u32 intel_sbi_read(struct drm_i915_private *i915, u16 reg,