This removes two anti-patterns:
- Locking shouldn't be used to synchronize with async work (of any
form, whether callbacks, workers or other threads). This is what the
mutex_lock/unlock seems to have been for in intel_csr_load_program.
Instead ordering should be ensured with the generic
wait_for_completion()/complete(). Or more specific functions
provided by the core kernel like e.g.
flush_work()/cancel_work_sync() in the case of synchronizing with a
work item.
- Don't invent own completion like the following code did with the
(already removed) wait_for(csr_load_status_get()) pattern - it's
really hard to get these right when you want them to be _really_
correct (and be fast) in all cases. Furthermore it's easier to read
code using the well-known primitives than new ones using
non-standard names.
Before enabling/disabling DC6 check if the firmware is loaded
successfully. This is guaranteed during runtime s/r, since otherwise we
don't enable RPM, but not during system s/r.
Note that it's still unclear whether we need to enable/disable DC6
during system s/r, until that's clarified, keep the current behavior and
enable/disable DC6.
Also after this patch there is a race during system s/r where the
firmware may not be loaded yet, that's addressed in an upcoming patch.
v2-v3:
- unchanged
v4:
- rebased on latest drm-intel-nightly
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
[imre: added code and note about checking if the firmware loaded ok,
before enabling/disabling it]
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Tested-by: Daniel Stone <daniels@collabora.com> # SKL
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447341037-2623-1-git-send-email-imre.deak@intel.com
spin_lock_init(&dev_priv->mmio_flip_lock);
mutex_init(&dev_priv->sb_lock);
mutex_init(&dev_priv->modeset_restore_lock);
- mutex_init(&dev_priv->csr_lock);
mutex_init(&dev_priv->av_mutex);
intel_pm_setup(dev);
static int skl_suspend_complete(struct drm_i915_private *dev_priv)
{
- enum csr_state state;
/* Enabling DC6 is not a hard requirement to enter runtime D3 */
skl_uninit_cdclk(dev_priv);
- /* TODO: wait for a completion event or
- * similar here instead of busy
- * waiting using wait_for function.
- */
- wait_for((state = intel_csr_load_status_get(dev_priv)) !=
- FW_UNINITIALIZED, 1000);
- if (state == FW_LOADED)
+ if (dev_priv->csr.dmc_payload)
skl_enable_dc6(dev_priv);
return 0;
{
struct drm_device *dev = dev_priv->dev;
- if (intel_csr_load_status_get(dev_priv) == FW_LOADED)
+ if (dev_priv->csr.dmc_payload)
skl_disable_dc6(dev_priv);
skl_init_cdclk(dev_priv);
#define CSR_VERSION_MAJOR(version) ((version) >> 16)
#define CSR_VERSION_MINOR(version) ((version) & 0xffff)
-enum csr_state {
- FW_UNINITIALIZED = 0,
- FW_LOADED,
- FW_FAILED
-};
-
struct intel_csr {
const char *fw_path;
uint32_t *dmc_payload;
uint32_t mmio_count;
uint32_t mmioaddr[8];
uint32_t mmiodata[8];
- enum csr_state state;
};
#define DEV_INFO_FOR_EACH_FLAG(func, sep) \
struct intel_csr csr;
- /* Display CSR-related protection */
- struct mutex csr_lock;
-
struct intel_gmbus gmbus[GMBUS_NUM_PINS];
/** gmbus_mutex protects against concurrent usage of the single hw gmbus
}
/**
- * intel_csr_load_status_get() - to get firmware loading status.
- * @dev_priv: i915 device.
- *
- * This function helps to get the firmware loading status.
- *
- * Return: Firmware loading status.
- */
-enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv)
-{
- enum csr_state state;
-
- mutex_lock(&dev_priv->csr_lock);
- state = dev_priv->csr.state;
- mutex_unlock(&dev_priv->csr_lock);
-
- return state;
-}
-
-/**
- * intel_csr_load_status_set() - help to set firmware loading status.
- * @dev_priv: i915 device.
- * @state: enumeration of firmware loading status.
- *
- * Set the firmware loading status.
- */
-void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
- enum csr_state state)
-{
- mutex_lock(&dev_priv->csr_lock);
- dev_priv->csr.state = state;
- mutex_unlock(&dev_priv->csr_lock);
-}
-
-/**
* intel_csr_load_program() - write the firmware from memory to register.
* @dev: drm device.
*
if (I915_READ(CSR_PROGRAM(0)))
return;
- mutex_lock(&dev_priv->csr_lock);
fw_size = dev_priv->csr.dmc_fw_size;
for (i = 0; i < fw_size; i++)
I915_WRITE(CSR_PROGRAM(i), payload[i]);
I915_WRITE(dev_priv->csr.mmioaddr[i],
dev_priv->csr.mmiodata[i]);
}
-
- dev_priv->csr.state = FW_LOADED;
- mutex_unlock(&dev_priv->csr_lock);
}
static void finish_csr_load(const struct firmware *fw, void *context)
CSR_VERSION_MAJOR(csr->version),
CSR_VERSION_MINOR(csr->version));
} else {
- intel_csr_load_status_set(dev_priv, FW_FAILED);
-
i915_firmware_load_error_print(csr->fw_path, 0);
}
csr->fw_path = I915_CSR_BXT;
else {
DRM_ERROR("Unexpected: no known CSR firmware for platform\n");
- intel_csr_load_status_set(dev_priv, FW_FAILED);
return;
}
&dev_priv->dev->pdev->dev,
GFP_KERNEL, dev_priv,
finish_csr_load);
- if (ret) {
+ if (ret)
i915_firmware_load_error_print(csr->fw_path, ret);
- intel_csr_load_status_set(dev_priv, FW_FAILED);
- }
}
/**
if (!HAS_CSR(dev))
return;
- intel_csr_load_status_set(dev_priv, FW_FAILED);
kfree(dev_priv->csr.dmc_payload);
}
/* intel_csr.c */
void intel_csr_ucode_init(struct drm_device *dev);
-enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv);
-void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
- enum csr_state state);
void intel_csr_load_program(struct drm_device *dev);
void intel_csr_ucode_fini(struct drm_device *dev);
} else {
if (enable_requested) {
if (IS_SKYLAKE(dev) &&
- (power_well->data == SKL_DISP_PW_1) &&
- (intel_csr_load_status_get(dev_priv) == FW_LOADED))
+ (power_well->data == SKL_DISP_PW_1))
DRM_DEBUG_KMS("Not Disabling PW1, dmc will handle\n");
else {
I915_WRITE(HSW_PWR_WELL_DRIVER, tmp & ~req_mask);
}
if (GEN9_ENABLE_DC5(dev) &&
- power_well->data == SKL_DISP_PW_2) {
- enum csr_state state;
- /* TODO: wait for a completion event or
- * similar here instead of busy
- * waiting using wait_for function.
- */
- wait_for((state = intel_csr_load_status_get(dev_priv)) !=
- FW_UNINITIALIZED, 1000);
- if (state != FW_LOADED)
- DRM_DEBUG("CSR firmware not ready (%d)\n",
- state);
- else
+ power_well->data == SKL_DISP_PW_2)
gen9_enable_dc5(dev_priv);
- }
}
}