From: Thierry Reding <treding@xxxxxxxxxx>
Simple framebuffers can be set up in system memory, which cannot be
requested and/or I/O remapped using the I/O resource helpers. Add a
separate code path that obtains system memory framebuffers from the
reserved memory region referenced in the memory-region property.
v2: make screen base a struct iosys_map to avoid sparse warnings
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
drivers/gpu/drm/tiny/simpledrm.c | 177 ++++++++++++++++++++++++-------
1 file changed, 141 insertions(+), 36 deletions(-)
diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c
index 18489779fb8a..cf36f67d22e4 100644
--- a/drivers/gpu/drm/tiny/simpledrm.c
+++ b/drivers/gpu/drm/tiny/simpledrm.c
@@ -2,6 +2,7 @@
#include <linux/clk.h>
#include <linux/of_clk.h>
+#include <linux/of_reserved_mem.h>
#include <linux/minmax.h>
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
@@ -207,7 +208,9 @@ struct simpledrm_device {
unsigned int pitch;
/* memory management */
- void __iomem *screen_base;
+ struct iosys_map screen_base;
+ phys_addr_t sysmem_start;
+ size_t sysmem_size;
/* modesetting */
uint32_t formats[8];
@@ -441,6 +444,106 @@ static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
}
#endif
+/*
+ * Memory management
+ */
+
+static int simpledrm_device_init_mm_sysmem(struct simpledrm_device *sdev, phys_addr_t start,
+ size_t size)
+{
+ struct drm_device *dev = &sdev->dev;
+ phys_addr_t end = start + size - 1;
+ void *screen_base;
+
+ drm_info(dev, "using system memory framebuffer at [%pa-%pa]\n", &start, &end);
+
+ screen_base = devm_memremap(dev->dev, start, size, MEMREMAP_WC);
+ if (!screen_base)
+ return -ENOMEM;
+
+ iosys_map_set_vaddr(&sdev->screen_base, screen_base);
+
+ return 0;
+}
+
+static int simpledrm_device_init_mm_io(struct simpledrm_device *sdev, phys_addr_t start,
+ size_t size)
+{
+ struct drm_device *dev = &sdev->dev;
+ phys_addr_t end = start + size - 1;
+ void __iomem *screen_base;
+ struct resource *mem;
+
+ drm_info(dev, "using I/O memory framebuffer at [%pa-%pa]\n", &start, &end);
+
+ mem = devm_request_mem_region(dev->dev, start, size, sdev->dev.driver->name);
+ if (!mem) {
+ /*
+ * We cannot make this fatal. Sometimes this comes from magic
+ * spaces our resource handlers simply don't know about. Use
+ * the I/O-memory resource as-is and try to map that instead.
+ */
+ drm_warn(dev, "could not acquire memory region [%pa-%pa]\n", &start, &end);
+ } else {
+ size = resource_size(mem);
+ start = mem->start;
+ }
+
+ screen_base = devm_ioremap_wc(dev->dev, start, size);
+ if (!screen_base)
+ return -ENOMEM;
+
+ iosys_map_set_vaddr_iomem(&sdev->screen_base, screen_base);
+
+ return 0;
+}
+
+static void simpledrm_device_exit_mm(void *data)
+{
+ struct simpledrm_device *sdev = data;
+ struct drm_device *dev = &sdev->dev;
+
+ of_reserved_mem_device_release(dev->dev);
+}
+
+static int simpledrm_device_init_mm(struct simpledrm_device *sdev)
+{
+ int (*init)(struct simpledrm_device *sdev, phys_addr_t start, size_t size);
+ struct drm_device *dev = &sdev->dev;
+ struct platform_device *pdev = to_platform_device(dev->dev);
+ phys_addr_t start, end;
+ size_t size;
+ int ret;
+
+ ret = of_reserved_mem_device_init_by_idx(dev->dev, dev->dev->of_node, 0);
+ if (ret) {
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ init = simpledrm_device_init_mm_io;
+ size = resource_size(res);
+ start = res->start;
+ } else {
+ devm_add_action_or_reset(dev->dev, simpledrm_device_exit_mm, sdev);
+ init = simpledrm_device_init_mm_sysmem;
+ start = sdev->sysmem_start;
+ size = sdev->sysmem_size;
+ }
+
+ end = start + size - 1;
+
+ ret = devm_aperture_acquire_from_firmware(dev, start, size);
+ if (ret) {
+ drm_err(dev, "could not acquire memory range [%pa-%pa]: %d\n", &start, &end, ret);
+ return ret;
+ }
+
+ return init(sdev, start, size);
+}
+
/*
* Modesetting
*/
@@ -491,15 +594,15 @@ static void simpledrm_primary_plane_helper_atomic_update(struct drm_plane *plane
drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
drm_atomic_for_each_plane_damage(&iter, &damage) {
- struct iosys_map dst = IOSYS_MAP_INIT_VADDR(sdev->screen_base);
struct drm_rect dst_clip = plane_state->dst;
if (!drm_rect_intersect(&dst_clip, &damage))
continue;
- iosys_map_incr(&dst, drm_fb_clip_offset(sdev->pitch, sdev->format, &dst_clip));
- drm_fb_blit(&dst, &sdev->pitch, sdev->format->format, shadow_plane_state->data, fb,
- &damage);
+ iosys_map_incr(&sdev->screen_base, drm_fb_clip_offset(sdev->pitch, sdev->format,
+ &dst_clip));
+ drm_fb_blit(&sdev->screen_base, &sdev->pitch, sdev->format->format,
+ shadow_plane_state->data, fb, &damage);
}
drm_dev_exit(idx);
@@ -518,7 +621,7 @@ static void simpledrm_primary_plane_helper_atomic_disable(struct drm_plane *plan
return;
/* Clear screen to black if disabled */
- memset_io(sdev->screen_base, 0, sdev->pitch * sdev->mode.vdisplay);
+ iosys_map_memset(&sdev->screen_base, 0, 0, sdev->pitch * sdev->mode.vdisplay);
drm_dev_exit(idx);
}
@@ -635,8 +738,6 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
struct drm_device *dev;
int width, height, stride;
const struct drm_format_info *format;
- struct resource *res, *mem;
- void __iomem *screen_base;
struct drm_plane *primary_plane;
struct drm_crtc *crtc;
struct drm_encoder *encoder;
@@ -706,35 +807,9 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
drm_dbg(dev, "framebuffer format=%p4cc, size=%dx%d, stride=%d byte\n",
&format->format, width, height, stride);
- /*
- * Memory management
- */
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return ERR_PTR(-EINVAL);
-
- ret = devm_aperture_acquire_from_firmware(dev, res->start, resource_size(res));
- if (ret) {
- drm_err(dev, "could not acquire memory range %pr: error %d\n", res, ret);
+ ret = simpledrm_device_init_mm(sdev);
+ if (ret)
return ERR_PTR(ret);
- }
-
- mem = devm_request_mem_region(&pdev->dev, res->start, resource_size(res), drv->name);
- if (!mem) {
- /*
- * We cannot make this fatal. Sometimes this comes from magic
- * spaces our resource handlers simply don't know about. Use
- * the I/O-memory resource as-is and try to map that instead.
- */
- drm_warn(dev, "could not acquire memory region %pr\n", res);
- mem = res;
- }
-
- screen_base = devm_ioremap_wc(&pdev->dev, mem->start, resource_size(mem));
- if (!screen_base)
- return ERR_PTR(-ENOMEM);
- sdev->screen_base = screen_base;
/*
* Modesetting
@@ -878,5 +953,35 @@ static struct platform_driver simpledrm_platform_driver = {
module_platform_driver(simpledrm_platform_driver);
+static int simple_framebuffer_device_init(struct reserved_mem *rmem, struct device *dev)
+{
+ struct simpledrm_device *sdev = dev_get_drvdata(dev);
+
+ sdev->sysmem_start = rmem->base;
+ sdev->sysmem_size = rmem->size;
+
+ return 0;
+}
+
+static void simple_framebuffer_device_release(struct reserved_mem *rmem, struct device *dev)
+{
+}
+
+static const struct reserved_mem_ops simple_framebuffer_ops = {
+ .device_init = simple_framebuffer_device_init,
+ .device_release = simple_framebuffer_device_release,
+};
+
+static int simple_framebuffer_init(struct reserved_mem *rmem)
+{
+ pr_info("framebuffer memory at %pa, size %lu bytes\n", &rmem->base,
+ (unsigned long)rmem->size);
+
+ rmem->ops = &simple_framebuffer_ops;
+
+ return 0;
+}
+RESERVEDMEM_OF_DECLARE(simple_framebuffer, "framebuffer", simple_framebuffer_init);
+
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL v2");
--
2.37.3
