At least sparc64 requires I/O-specific access to framebuffers. This patch updates the fbdev console accordingly.
For drivers with direct access to the framebuffer memory, the callback functions in struct fb_ops test for the type of memory and call the rsp fb_sys_ of fb_cfb_ functions.
For drivers that employ a shadow buffer, fbdev's blit function retrieves the framebuffer address as struct dma_buf_map, and uses dma_buf_map interfaces to access the buffer.
The bochs driver on sparc64 uses a workaround to flag the framebuffer as I/O memory and avoid a HW exception. With the introduction of struct dma_buf_map, this is not required any longer. The patch removes the rsp code from both, bochs and fbdev.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de --- drivers/gpu/drm/bochs/bochs_kms.c | 1 - drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- include/drm/drm_mode_config.h | 12 -- include/linux/dma-buf-map.h | 72 ++++++++-- 4 files changed, 265 insertions(+), 37 deletions(-)
diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c +++ b/drivers/gpu/drm/bochs/bochs_kms.c @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) bochs->dev->mode_config.preferred_depth = 24; bochs->dev->mode_config.prefer_shadow = 0; bochs->dev->mode_config.prefer_shadow_fbdev = 1; - bochs->dev->mode_config.fbdev_use_iomem = true; bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true;
bochs->dev->mode_config.funcs = &bochs_mode_funcs; diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 343a292f2c7c..f345a314a437 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -388,24 +388,22 @@ static void drm_fb_helper_resume_worker(struct work_struct *work) }
static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper, - struct drm_clip_rect *clip) + struct drm_clip_rect *clip, + struct dma_buf_map *dst) { struct drm_framebuffer *fb = fb_helper->fb; unsigned int cpp = fb->format->cpp[0]; size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; void *src = fb_helper->fbdev->screen_buffer + offset; - void *dst = fb_helper->buffer->map.vaddr + offset; size_t len = (clip->x2 - clip->x1) * cpp; unsigned int y;
- for (y = clip->y1; y < clip->y2; y++) { - if (!fb_helper->dev->mode_config.fbdev_use_iomem) - memcpy(dst, src, len); - else - memcpy_toio((void __iomem *)dst, src, len); + dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */
+ for (y = clip->y1; y < clip->y2; y++) { + dma_buf_map_memcpy_to(dst, src, len); + dma_buf_map_incr(dst, fb->pitches[0]); src += fb->pitches[0]; - dst += fb->pitches[0]; } }
@@ -433,8 +431,9 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map); if (ret) return; - drm_fb_helper_dirty_blit_real(helper, &clip_copy); + drm_fb_helper_dirty_blit_real(helper, &clip_copy, &map); } + if (helper->fb->funcs->dirty) helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1); @@ -771,6 +770,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info *info, } EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
+static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *dst; + u8 __iomem *src; + int c, err = 0; + unsigned long total_size; + unsigned long alloc_size; + ssize_t ret = 0; + + if (info->state != FBINFO_STATE_RUNNING) + return -EPERM; + + total_size = info->screen_size; + + if (total_size == 0) + total_size = info->fix.smem_len; + + if (p >= total_size) + return 0; + + if (count >= total_size) + count = total_size; + + if (count + p > total_size) + count = total_size - p; + + src = (u8 __iomem *)(info->screen_base + p); + + alloc_size = min(count, PAGE_SIZE); + + dst = kmalloc(alloc_size, GFP_KERNEL); + if (!dst) + return -ENOMEM; + + while (count) { + c = min(count, alloc_size); + + memcpy_fromio(dst, src, c); + if (copy_to_user(buf, dst, c)) { + err = -EFAULT; + break; + } + + src += c; + *ppos += c; + buf += c; + ret += c; + count -= c; + } + + kfree(dst); + + if (err) + return err; + + return ret; +} + +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *src; + u8 __iomem *dst; + int c, err = 0; + unsigned long total_size; + unsigned long alloc_size; + ssize_t ret = 0; + + if (info->state != FBINFO_STATE_RUNNING) + return -EPERM; + + total_size = info->screen_size; + + if (total_size == 0) + total_size = info->fix.smem_len; + + if (p > total_size) + return -EFBIG; + + if (count > total_size) { + err = -EFBIG; + count = total_size; + } + + if (count + p > total_size) { + /* + * The framebuffer is too small. We do the + * copy operation, but return an error code + * afterwards. Taken from fbdev. + */ + if (!err) + err = -ENOSPC; + count = total_size - p; + } + + alloc_size = min(count, PAGE_SIZE); + + src = kmalloc(alloc_size, GFP_KERNEL); + if (!src) + return -ENOMEM; + + dst = (u8 __iomem *)(info->screen_base + p); + + while (count) { + c = min(count, alloc_size); + + if (copy_from_user(src, buf, c)) { + err = -EFAULT; + break; + } + memcpy_toio(dst, src, c); + + dst += c; + *ppos += c; + buf += c; + ret += c; + count -= c; + } + + kfree(src); + + if (err) + return err; + + return ret; +} + /** * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect * @info: fbdev registered by the helper @@ -2043,6 +2172,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) return -ENODEV; }
+static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, + size_t count, loff_t *ppos) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + return drm_fb_helper_sys_read(info, buf, count, ppos); + else + return drm_fb_helper_cfb_read(info, buf, count, ppos); +} + +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + return drm_fb_helper_sys_write(info, buf, count, ppos); + else + return drm_fb_helper_cfb_write(info, buf, count, ppos); +} + +static void drm_fbdev_fb_fillrect(struct fb_info *info, + const struct fb_fillrect *rect) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_fillrect(info, rect); + else + drm_fb_helper_cfb_fillrect(info, rect); +} + +static void drm_fbdev_fb_copyarea(struct fb_info *info, + const struct fb_copyarea *area) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_copyarea(info, area); + else + drm_fb_helper_cfb_copyarea(info, area); +} + +static void drm_fbdev_fb_imageblit(struct fb_info *info, + const struct fb_image *image) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_imageblit(info, image); + else + drm_fb_helper_cfb_imageblit(info, image); +} + static const struct fb_ops drm_fbdev_fb_ops = { .owner = THIS_MODULE, DRM_FB_HELPER_DEFAULT_OPS, @@ -2050,11 +2239,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { .fb_release = drm_fbdev_fb_release, .fb_destroy = drm_fbdev_fb_destroy, .fb_mmap = drm_fbdev_fb_mmap, - .fb_read = drm_fb_helper_sys_read, - .fb_write = drm_fb_helper_sys_write, - .fb_fillrect = drm_fb_helper_sys_fillrect, - .fb_copyarea = drm_fb_helper_sys_copyarea, - .fb_imageblit = drm_fb_helper_sys_imageblit, + .fb_read = drm_fbdev_fb_read, + .fb_write = drm_fbdev_fb_write, + .fb_fillrect = drm_fbdev_fb_fillrect, + .fb_copyarea = drm_fbdev_fb_copyarea, + .fb_imageblit = drm_fbdev_fb_imageblit, };
static struct fb_deferred_io drm_fbdev_defio = { diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index 5ffbb4ed5b35..ab424ddd7665 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -877,18 +877,6 @@ struct drm_mode_config { */ bool prefer_shadow_fbdev;
- /** - * @fbdev_use_iomem: - * - * Set to true if framebuffer reside in iomem. - * When set to true memcpy_toio() is used when copying the framebuffer in - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). - * - * FIXME: This should be replaced with a per-mapping is_iomem - * flag (like ttm does), and then used everywhere in fbdev code. - */ - bool fbdev_use_iomem; - /** * @quirk_addfb_prefer_xbgr_30bpp: * diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h index 2e8bbecb5091..6ca0f304dda2 100644 --- a/include/linux/dma-buf-map.h +++ b/include/linux/dma-buf-map.h @@ -32,6 +32,14 @@ * accessing the buffer. Use the returned instance and the helper functions * to access the buffer's memory in the correct way. * + * The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers are + * actually independent from the dma-buf infrastructure. When sharing buffers + * among devices, drivers have to know the location of the memory to access + * the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>` + * solves this problem for dma-buf and its users. If other drivers or + * sub-systems require similar functionality, the type could be generalized + * and moved to a more prominent header file. + * * Open-coding access to :c:type:`struct dma_buf_map <dma_buf_map>` is * considered bad style. Rather then accessing its fields directly, use one * of the provided helper functions, or implement your own. For example, @@ -51,6 +59,14 @@ * * dma_buf_map_set_vaddr_iomem(&map. 0xdeadbeaf); * + * Instances of struct dma_buf_map do not have to be cleaned up, but + * can be cleared to NULL with dma_buf_map_clear(). Cleared mappings + * always refer to system memory. + * + * .. code-block:: c + * + * dma_buf_map_clear(&map); + * * Test if a mapping is valid with either dma_buf_map_is_set() or * dma_buf_map_is_null(). * @@ -73,17 +89,19 @@ * if (dma_buf_map_is_equal(&sys_map, &io_map)) * // always false * - * Instances of struct dma_buf_map do not have to be cleaned up, but - * can be cleared to NULL with dma_buf_map_clear(). Cleared mappings - * always refer to system memory. + * A set up instance of struct dma_buf_map can be used to access or manipulate + * the buffer memory. Depending on the location of the memory, the provided + * helpers will pick the correct operations. Data can be copied into the memory + * with dma_buf_map_memcpy_to(). The address can be manipulated with + * dma_buf_map_incr(). * - * The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers are - * actually independent from the dma-buf infrastructure. When sharing buffers - * among devices, drivers have to know the location of the memory to access - * the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>` - * solves this problem for dma-buf and its users. If other drivers or - * sub-systems require similar functionality, the type could be generalized - * and moved to a more prominent header file. + * .. code-block:: c + * + * const void *src = ...; // source buffer + * size_t len = ...; // length of src + * + * dma_buf_map_memcpy_to(&map, src, len); + * dma_buf_map_incr(&map, len); // go to first byte after the memcpy */
/** @@ -210,4 +228,38 @@ static inline void dma_buf_map_clear(struct dma_buf_map *map) } }
+/** + * dma_buf_map_memcpy_to - Memcpy into dma-buf mapping + * @dst: The dma-buf mapping structure + * @src: The source buffer + * @len: The number of byte in src + * + * Copies data into a dma-buf mapping. The source buffer is in system + * memory. Depending on the buffer's location, the helper picks the correct + * method of accessing the memory. + */ +static inline void dma_buf_map_memcpy_to(struct dma_buf_map *dst, const void *src, size_t len) +{ + if (dst->is_iomem) + memcpy_toio(dst->vaddr_iomem, src, len); + else + memcpy(dst->vaddr, src, len); +} + +/** + * dma_buf_map_incr - Increments the address stored in a dma-buf mapping + * @map: The dma-buf mapping structure + * @incr: The number of bytes to increment + * + * Increments the address stored in a dma-buf mapping. Depending on the + * buffer's location, the correct value will be updated. + */ +static inline void dma_buf_map_incr(struct dma_buf_map *map, size_t incr) +{ + if (map->is_iomem) + map->vaddr_iomem += incr; + else + map->vaddr += incr; +} + #endif /* __DMA_BUF_MAP_H__ */