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Hi Liviu, Thanks for your feedback. All good stuff... On 20 September 2012 11:24, Liviu Dudau [off-list ref] wrote:
On Wed, Sep 19, 2012 at 05:04:24PM +0100, Ryan Harkin wrote:quoted
Add support to parse the display configuration from device tree. If the board does not provide platform specific functions in the struct clcd_board contained with the amba device info, then defaults are provided by the driver. The device tree configuration can either ask for a DMA setup or provide a framebuffer address to be remapped into the driver. Signed-off-by: Ryan Harkin <redacted> --- drivers/video/amba-clcd.c | 253 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+)diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c index 0a2cce7..01dbad1 100644 --- a/drivers/video/amba-clcd.c +++ b/drivers/video/amba-clcd.c@@ -16,7 +16,10 @@ #include <linux/string.h> #include <linux/slab.h> #include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/memblock.h> #include <linux/mm.h> +#include <linux/of.h> #include <linux/fb.h> #include <linux/init.h> #include <linux/ioport.h>@@ -391,6 +394,19 @@ static int clcdfb_blank(int blank_mode, struct fb_info *info) } return 0; } +int clcdfb_mmap_dma(struct clcd_fb *fb, struct vm_area_struct *vma) +{ + return dma_mmap_writecombine(&fb->dev->dev, vma, + fb->fb.screen_base, + fb->fb.fix.smem_start, + fb->fb.fix.smem_len);
I see what you mean. I'm happy to swap them if there are no objections.
quoted
+ const char *string; + int count, i, ret = 0; + + count = of_property_count_strings(node, name); + if (count >= 0) + for (i = 0; i < count; i++) + if (of_property_read_string_index(node, name, i, + &string) = 0) + ret |= parse_setting(lookup, string); + return ret; +} + +int get_val(struct device_node *node, const char *string) +{ + u32 ret = 0; + + if (of_property_read_u32(node, string, &ret)) + ret = -1; + return ret; +} + +struct clcd_panel *getPanel(struct device_node *node) +{ + static struct clcd_panel panel; + + panel.mode.refresh = get_val(node, "refresh"); + panel.mode.xres = get_val(node, "xres"); + panel.mode.yres = get_val(node, "yres"); + panel.mode.pixclock = get_val(node, "pixclock"); + panel.mode.left_margin = get_val(node, "left_margin"); + panel.mode.right_margin = get_val(node, "right_margin"); + panel.mode.upper_margin = get_val(node, "upper_margin"); + panel.mode.lower_margin = get_val(node, "lower_margin"); + panel.mode.hsync_len = get_val(node, "hsync_len"); + panel.mode.vsync_len = get_val(node, "vsync_len"); + panel.mode.sync = get_val(node, "sync"); + panel.bpp = get_val(node, "bpp"); + panel.width = (signed short) get_val(node, "width"); + panel.height = (signed short) get_val(node, "height");
Agree.
quoted
+static int clcdfb_dt_init(struct clcd_fb *fb) +{ + int err = 0; + struct device_node *node; + const char *mode; + dma_addr_t dma; + u32 use_dma; + const __be32 *prop; + int len, na, ns; + phys_addr_t fb_base, fb_size; + + node = fb->dev->dev.of_node; + if (!node) + return -ENODEV; + + na = of_n_addr_cells(node); + ns = of_n_size_cells(node); + + if (WARN_ON(of_property_read_string(node, "mode", &mode))) + return -ENODEV; + + fb->panel = clcdfb_get_panel(mode); + if (!fb->panel) + return -EINVAL; + fb->fb.fix.smem_len = fb->panel->mode.xres * fb->panel->mode.yres * 2; + + if (of_property_read_u32(node, "use_dma", &use_dma))I haven't seen any documentation for this property. What's the intended use?
Good point. Sorry for my ignorance, but is there a place I should put such documentation? When the A9 CoreTile uses the on-tile CLCD controller, it can use DMA to handle the framebuffer. DMA is not available to the motherboard CLCD controller. I was trying to keep the properties simple, but they are more complex than just the two settings: use_dma and framebuffer. If use_dma is specified, the framebuffer property is not used; in this case, the framebuffer is allocated by the DMA framework and the framebuffer property is ignored. If use_dma is not present or is set to <0>, the code uses the framebuffer property to specify the address.
quoted
+ use_dma = 0; + if (use_dma) { + fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, + fb->fb.fix.smem_len, &dma, GFP_KERNEL); + if (!fb->fb.screen_base) { + pr_err("CLCD: unable to map framebuffer\n"); + err = -ENOMEM; + } else + fb->fb.fix.smem_start = dma; + } else { + prop = of_get_property(node, "framebuffer", &len); + if (WARN_ON(!prop || len < (na + ns) * sizeof(*prop))) + return -EINVAL; + fb_base = of_read_number(prop, na); + fb_size = of_read_number(prop + na, ns); + + if (memblock_remove(fb_base, fb_size) != 0) + return -EINVAL; + + fb->fb.fix.smem_start = fb_base; + fb->fb.screen_base = ioremap_wc(fb->fb.fix.smem_start, fb_size); + } + return err; +} +#endif /* CONFIG_OF */ + static int clcdfb_probe(struct amba_device *dev, const struct amba_id *id) { struct clcd_board *board = dev->dev.platform_data; struct clcd_fb *fb; int ret; +#ifdef CONFIG_OF + if (dev->dev.of_node) { + const __be32 *prop; + int len, na, ns; + phys_addr_t reg_base; + + na = of_n_addr_cells(dev->dev.of_node);