The lock for the I/O registers is only relevant during mode-setting
operations. It protects the registers from concurrent access from
reading EDID information.
Reduce lock coverage to mode setting, rename the lock and move it
entirely into the mode-setting code. No functional changes, as the
I/O lock was never used for anything else than mode setting.
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Reviewed-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
---
drivers/gpu/drm/ast/ast_drv.h | 3 ++-
drivers/gpu/drm/ast/ast_main.c | 4 ----
drivers/gpu/drm/ast/ast_mode.c | 26 +++++++++++++++-----------
3 files changed, 17 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 2aee32344f4a2..8b5d6e2954858 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -181,7 +181,6 @@ to_ast_sil164_connector(struct drm_connector *connector)
struct ast_device {
struct drm_device base;
- struct mutex ioregs_lock; /* Protects access to I/O registers in ioregs */
void __iomem *regs;
void __iomem *ioregs;
void __iomem *dp501_fw_buf;
@@ -196,6 +195,8 @@ struct ast_device {
unsigned long vram_size;
unsigned long vram_fb_available;
+ struct mutex modeset_lock; /* Protects access to modeset I/O registers in ioregs */
+
struct ast_plane primary_plane;
struct ast_plane cursor_plane;
struct drm_crtc crtc;
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index f4ab40e22ceac..445cf47871a43 100644
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -440,10 +440,6 @@ struct ast_device *ast_device_create(const struct drm_driver *drv,
pci_set_drvdata(pdev, dev);
- ret = drmm_mutex_init(dev, &ast->ioregs_lock);
- if (ret)
- return ERR_PTR(ret);
-
ast->regs = pcim_iomap(pdev, 1, 0);
if (!ast->regs)
return ERR_PTR(-EIO);
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index cb96149842851..817c291aef2c4 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1358,13 +1358,13 @@ static int ast_vga_connector_helper_get_modes(struct drm_connector *connector)
* Protect access to I/O registers from concurrent modesetting
* by acquiring the I/O-register lock.
*/
- mutex_lock(&ast->ioregs_lock);
+ mutex_lock(&ast->modeset_lock);
edid = drm_get_edid(connector, &ast_vga_connector->i2c->adapter);
if (!edid)
goto err_mutex_unlock;
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
count = drm_add_edid_modes(connector, edid);
kfree(edid);
@@ -1372,7 +1372,7 @@ static int ast_vga_connector_helper_get_modes(struct drm_connector *connector)
return count;
err_mutex_unlock:
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
err_drm_connector_update_edid_property:
drm_connector_update_edid_property(connector, NULL);
return 0;
@@ -1464,13 +1464,13 @@ static int ast_sil164_connector_helper_get_modes(struct drm_connector *connector
* Protect access to I/O registers from concurrent modesetting
* by acquiring the I/O-register lock.
*/
- mutex_lock(&ast->ioregs_lock);
+ mutex_lock(&ast->modeset_lock);
edid = drm_get_edid(connector, &ast_sil164_connector->i2c->adapter);
if (!edid)
goto err_mutex_unlock;
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
count = drm_add_edid_modes(connector, edid);
kfree(edid);
@@ -1478,7 +1478,7 @@ static int ast_sil164_connector_helper_get_modes(struct drm_connector *connector
return count;
err_mutex_unlock:
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
err_drm_connector_update_edid_property:
drm_connector_update_edid_property(connector, NULL);
return 0;
@@ -1670,13 +1670,13 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector)
* Protect access to I/O registers from concurrent modesetting
* by acquiring the I/O-register lock.
*/
- mutex_lock(&ast->ioregs_lock);
+ mutex_lock(&ast->modeset_lock);
succ = ast_astdp_read_edid(connector->dev, edid);
if (succ < 0)
goto err_mutex_unlock;
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
drm_connector_update_edid_property(connector, edid);
count = drm_add_edid_modes(connector, edid);
@@ -1685,7 +1685,7 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector)
return count;
err_mutex_unlock:
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
kfree(edid);
err_drm_connector_update_edid_property:
drm_connector_update_edid_property(connector, NULL);
@@ -1827,9 +1827,9 @@ static void ast_mode_config_helper_atomic_commit_tail(struct drm_atomic_state *s
* display modes. Protect access to I/O registers by acquiring
* the I/O-register lock. Released in atomic_flush().
*/
- mutex_lock(&ast->ioregs_lock);
+ mutex_lock(&ast->modeset_lock);
drm_atomic_helper_commit_tail_rpm(state);
- mutex_unlock(&ast->ioregs_lock);
+ mutex_unlock(&ast->modeset_lock);
}
static const struct drm_mode_config_helper_funcs ast_mode_config_helper_funcs = {
@@ -1866,6 +1866,10 @@ int ast_mode_config_init(struct ast_device *ast)
struct drm_device *dev = &ast->base;
int ret;
+ ret = drmm_mutex_init(dev, &ast->modeset_lock);
+ if (ret)
+ return ret;
+
ret = drmm_mode_config_init(dev);
if (ret)
return ret;
--
2.42.0
