We register the simplekms device with the DRM platform helpers. A
native driver for the graphics hardware will kick-out the simpledrm
driver before taking over the device.
v2:
* adapt to aperture changes
* use drm_dev_unplug() and drm_dev_enter/exit()
* don't split error string
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Tested-by: nerdopolis <bluescreen_avenger@xxxxxxxxxxx>
---
drivers/gpu/drm/tiny/Kconfig | 1 +
drivers/gpu/drm/tiny/simpledrm.c | 83 ++++++++++++++++++++++++++++++--
2 files changed, 81 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
index d46f95d9196d..5b72dd8e93f9 100644
--- a/drivers/gpu/drm/tiny/Kconfig
+++ b/drivers/gpu/drm/tiny/Kconfig
@@ -41,6 +41,7 @@ config DRM_GM12U320
config DRM_SIMPLEDRM
tristate "Simple framebuffer driver"
depends on DRM
+ select DRM_APERTURE
select DRM_GEM_SHMEM_HELPER
select DRM_KMS_HELPER
help
diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c
index 2e27eeb791a1..67d33af19086 100644
--- a/drivers/gpu/drm/tiny/simpledrm.c
+++ b/drivers/gpu/drm/tiny/simpledrm.c
@@ -5,7 +5,9 @@
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
+#include <linux/spinlock.h>
+#include <drm/drm_aperture.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_connector.h>
#include <drm/drm_damage_helper.h>
@@ -37,6 +39,12 @@
#define SIMPLEDRM_MODE(hd, vd) \
DRM_SIMPLE_MODE(hd, vd, RES_MM(hd), RES_MM(vd))
+/*
+ * Protects the platform device's drvdata against
+ * concurrent manipulation.
+ */
+static DEFINE_SPINLOCK(simpledrm_drvdata_lock);
+
/*
* Helpers for simplefb
*/
@@ -515,16 +523,53 @@ static int simpledrm_device_init_fb(struct simpledrm_device *sdev)
* Memory management
*/
+static void simpledrm_aperture_detach(struct drm_device *dev, resource_size_t base,
+ resource_size_t size)
+{
+ struct simpledrm_device *sdev = simpledrm_device_of_dev(dev);
+ struct platform_device *pdev = sdev->pdev;
+
+ if (WARN_ON(drm_dev_is_unplugged(dev)))
+ return; /* BUG: driver already got detached */
+
+ /*
+ * If simpledrm gets detached from the aperture, it's like unplugging
+ * the device. So call drm_dev_unplug().
+ */
+ drm_dev_unplug(dev);
+
+ spin_lock(&simpledrm_drvdata_lock);
+ sdev = platform_get_drvdata(pdev);
+ platform_set_drvdata(pdev, NULL); /* required; see simpledrm_remove() */
+ spin_unlock(&simpledrm_drvdata_lock);
+}
+
+static const struct drm_aperture_funcs simpledrm_aperture_funcs = {
+ .detach = simpledrm_aperture_detach,
+};
+
static int simpledrm_device_init_mm(struct simpledrm_device *sdev)
{
+ struct drm_device *dev = &sdev->dev;
struct platform_device *pdev = sdev->pdev;
struct resource *mem;
+ struct drm_aperture *ap;
void __iomem *screen_base;
+ int ret;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem)
return -EINVAL;
+ ap = devm_aperture_acquire(dev, mem->start, resource_size(mem),
+ &simpledrm_aperture_funcs);
+ if (IS_ERR(ap)) {
+ ret = PTR_ERR(ap);
+ drm_err(dev, "could not acquire memory range [0x%llx:0x%llx]: error %d\n",
+ mem->start, mem->end, ret);
+ return ret;
+ }
+
screen_base = devm_ioremap_wc(&pdev->dev, mem->start,
resource_size(mem));
if (!screen_base)
@@ -625,12 +670,18 @@ simpledrm_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
struct drm_framebuffer *fb = plane_state->fb;
void *vmap = shadow_plane_state->map[0].vaddr; /* TODO: Use mapping abstraction properly */
+ struct drm_device *dev = &sdev->dev;
+ int idx;
if (!fb)
return;
+ if (!drm_dev_enter(dev, &idx))
+ return;
+
drm_fb_blit_dstclip(sdev->screen_base, sdev->pitch,
sdev->format->format, vmap, fb);
+ drm_dev_exit(idx);
}
static void
@@ -642,7 +693,9 @@ simpledrm_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
void *vmap = shadow_plane_state->map[0].vaddr; /* TODO: Use mapping abstraction properly */
struct drm_framebuffer *fb = plane_state->fb;
+ struct drm_device *dev = &sdev->dev;
struct drm_rect clip;
+ int idx;
if (!fb)
return;
@@ -650,8 +703,13 @@ simpledrm_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
if (!drm_atomic_helper_damage_merged(old_plane_state, plane_state, &clip))
return;
+ if (!drm_dev_enter(dev, &idx))
+ return;
+
drm_fb_blit_rect_dstclip(sdev->screen_base, sdev->pitch,
sdev->format->format, vmap, fb, &clip);
+
+ drm_dev_exit(idx);
}
static const struct drm_simple_display_pipe_funcs
@@ -826,10 +884,29 @@ static int simpledrm_probe(struct platform_device *pdev)
static int simpledrm_remove(struct platform_device *pdev)
{
- struct simpledrm_device *sdev = platform_get_drvdata(pdev);
- struct drm_device *dev = &sdev->dev;
+ struct simpledrm_device *sdev;
+
+ spin_lock(&simpledrm_drvdata_lock);
+ sdev = platform_get_drvdata(pdev);
+ platform_set_drvdata(pdev, NULL);
+ spin_unlock(&simpledrm_drvdata_lock);
+
+ /*
+ * The platform driver shares its reference to dev with the
+ * platform helpers for apertures. That reference is either
+ * released here when unloading the driver; or it's released
+ * when the driver gets kicked out by another driver. In the
+ * latter case, the aperture release routine clears the data
+ * field of the platform device.
+ *
+ * Therefore, sdev being NULL is a valid state if the driver
+ * has been kicked out by another DRM driver. In this case,
+ * it's all been cleaned up and we can return immediately.
+ */
+ if (!sdev)
+ return 0;
- drm_dev_unregister(dev);
+ drm_dev_unplug(&sdev->dev);
return 0;
}
--
2.30.1
