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. Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> --- drivers/gpu/drm/tiny/simpledrm.c | 166 +++++++++++++++++++++++++------ 1 file changed, 135 insertions(+), 31 deletions(-) diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c index a81f91814595..16377b39f012 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> @@ -218,6 +219,8 @@ struct simpledrm_device { /* memory management */ void __iomem *screen_base; + phys_addr_t sysmem_start; + size_t sysmem_size; /* modesetting */ uint32_t formats[8]; @@ -451,6 +454,100 @@ 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; + + drm_info(dev, "using system memory framebuffer at [%pa-%pa]\n", &start, &end); + + sdev->screen_base = devm_memremap(dev->dev, start, size, MEMREMAP_WC); + if (!sdev->screen_base) + return -ENOMEM; + + 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; + 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; + } + + sdev->screen_base = devm_ioremap_wc(dev->dev, start, size); + if (!sdev->screen_base) + return -ENOMEM; + + 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 */ @@ -511,13 +608,18 @@ static void simpledrm_primary_plane_helper_atomic_update(struct drm_plane *plane struct drm_framebuffer *fb = plane_state->fb; struct drm_device *dev = plane->dev; struct simpledrm_device *sdev = simpledrm_device_of_dev(dev); - struct iosys_map dst = IOSYS_MAP_INIT_VADDR(sdev->screen_base); struct drm_rect src_clip, dst_clip; + struct iosys_map dst; int idx; if (!fb) return; + if (sdev->sysmem_size == 0) + iosys_map_set_vaddr_iomem(&dst, sdev->screen_base); + else + iosys_map_set_vaddr(&dst, sdev->screen_base); + if (!drm_atomic_helper_damage_merged(old_plane_state, plane_state, &src_clip)) return; @@ -721,8 +823,6 @@ 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; @@ -790,35 +890,9 @@ 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 @@ -959,5 +1033,35 @@ 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"); -- 2.37.2