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Diffstat (limited to 'target/linux/brcm2708/patches-3.14/0026-bcm2708_fb-DMA-acceleration-for-fb_copyarea.patch')
-rw-r--r--target/linux/brcm2708/patches-3.14/0026-bcm2708_fb-DMA-acceleration-for-fb_copyarea.patch451
1 files changed, 0 insertions, 451 deletions
diff --git a/target/linux/brcm2708/patches-3.14/0026-bcm2708_fb-DMA-acceleration-for-fb_copyarea.patch b/target/linux/brcm2708/patches-3.14/0026-bcm2708_fb-DMA-acceleration-for-fb_copyarea.patch
deleted file mode 100644
index 5707137ab1..0000000000
--- a/target/linux/brcm2708/patches-3.14/0026-bcm2708_fb-DMA-acceleration-for-fb_copyarea.patch
+++ /dev/null
@@ -1,451 +0,0 @@
-From c2731f282848af32425043a2df88c1289538983e Mon Sep 17 00:00:00 2001
-From: Siarhei Siamashka <siarhei.siamashka@gmail.com>
-Date: Mon, 17 Jun 2013 16:00:25 +0300
-Subject: [PATCH 26/54] bcm2708_fb: DMA acceleration for fb_copyarea
-
-Based on http://www.raspberrypi.org/phpBB3/viewtopic.php?p=62425#p62425
-Also used Simon's dmaer_master module as a reference for tweaking DMA
-settings for better performance.
-
-For now busylooping only. IRQ support might be added later.
-With non-overclocked Raspberry Pi, the performance is ~360 MB/s
-for simple copy or ~260 MB/s for two-pass copy (used when dragging
-windows to the right).
-
-In the case of using DMA channel 0, the performance improves
-to ~440 MB/s.
-
-For comparison, VFP optimized CPU copy can only do ~114 MB/s in
-the same conditions (hindered by reading uncached source buffer).
-
-Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
-
-bcm2708_fb: report number of dma copies
-
-Add a counter (exported via debugfs) reporting the
-number of dma copies that the framebuffer driver
-has done, in order to help evaluate different
-optimization strategies.
-
-Signed-off-by: Luke Diamand <luked@broadcom.com>
-
-bcm2708_fb: use IRQ for DMA copies
-
-The copyarea ioctl() uses DMA to speed things along. This
-was busy-waiting for completion. This change supports using
-an interrupt instead for larger transfers. For small
-transfers, busy-waiting is still likely to be faster.
-
-Signed-off-by: Luke Diamand <luke@diamand.org>
----
- arch/arm/mach-bcm2708/dma.c | 8 +
- arch/arm/mach-bcm2708/include/mach/dma.h | 2 +
- drivers/video/bcm2708_fb.c | 273 ++++++++++++++++++++++++++++++-
- 3 files changed, 278 insertions(+), 5 deletions(-)
-
---- a/arch/arm/mach-bcm2708/dma.c
-+++ b/arch/arm/mach-bcm2708/dma.c
-@@ -83,6 +83,14 @@ extern void bcm_dma_wait_idle(void __iom
-
- EXPORT_SYMBOL_GPL(bcm_dma_start);
-
-+extern bool bcm_dma_is_busy(void __iomem *dma_chan_base)
-+{
-+ dsb();
-+
-+ return readl(dma_chan_base + BCM2708_DMA_CS) & BCM2708_DMA_ACTIVE;
-+}
-+EXPORT_SYMBOL_GPL(bcm_dma_is_busy);
-+
- /* Complete an ongoing DMA (assuming its results are to be ignored)
- Does nothing if there is no DMA in progress.
- This routine waits for the current AXI transfer to complete before
---- a/arch/arm/mach-bcm2708/include/mach/dma.h
-+++ b/arch/arm/mach-bcm2708/include/mach/dma.h
-@@ -62,11 +62,13 @@ struct bcm2708_dma_cb {
- unsigned long next;
- unsigned long pad[2];
- };
-+struct scatterlist;
-
- extern int bcm_sg_suitable_for_dma(struct scatterlist *sg_ptr, int sg_len);
- extern void bcm_dma_start(void __iomem *dma_chan_base,
- dma_addr_t control_block);
- extern void bcm_dma_wait_idle(void __iomem *dma_chan_base);
-+extern bool bcm_dma_is_busy(void __iomem *dma_chan_base);
- extern int /*rc*/ bcm_dma_abort(void __iomem *dma_chan_base);
-
- /* When listing features we can ask for when allocating DMA channels give
---- a/drivers/video/bcm2708_fb.c
-+++ b/drivers/video/bcm2708_fb.c
-@@ -21,13 +21,16 @@
- #include <linux/mm.h>
- #include <linux/fb.h>
- #include <linux/init.h>
-+#include <linux/interrupt.h>
- #include <linux/ioport.h>
- #include <linux/list.h>
- #include <linux/platform_device.h>
- #include <linux/clk.h>
- #include <linux/printk.h>
- #include <linux/console.h>
-+#include <linux/debugfs.h>
-
-+#include <mach/dma.h>
- #include <mach/platform.h>
- #include <mach/vcio.h>
-
-@@ -51,6 +54,10 @@ static int fbheight = 480; /* module par
- static int fbdepth = 16; /* module parameter */
- static int fbswap = 0; /* module parameter */
-
-+static u32 dma_busy_wait_threshold = 1<<15;
-+module_param(dma_busy_wait_threshold, int, 0644);
-+MODULE_PARM_DESC(dma_busy_wait_threshold, "Busy-wait for DMA completion below this area");
-+
- /* this data structure describes each frame buffer device we find */
-
- struct fbinfo_s {
-@@ -62,16 +69,73 @@ struct fbinfo_s {
- u16 cmap[256];
- };
-
-+struct bcm2708_fb_stats {
-+ struct debugfs_regset32 regset;
-+ u32 dma_copies;
-+ u32 dma_irqs;
-+};
-+
- struct bcm2708_fb {
- struct fb_info fb;
- struct platform_device *dev;
- struct fbinfo_s *info;
- dma_addr_t dma;
- u32 cmap[16];
-+ int dma_chan;
-+ int dma_irq;
-+ void __iomem *dma_chan_base;
-+ void *cb_base; /* DMA control blocks */
-+ dma_addr_t cb_handle;
-+ struct dentry *debugfs_dir;
-+ wait_queue_head_t dma_waitq;
-+ struct bcm2708_fb_stats stats;
- };
-
- #define to_bcm2708(info) container_of(info, struct bcm2708_fb, fb)
-
-+static void bcm2708_fb_debugfs_deinit(struct bcm2708_fb *fb)
-+{
-+ debugfs_remove_recursive(fb->debugfs_dir);
-+ fb->debugfs_dir = NULL;
-+}
-+
-+static int bcm2708_fb_debugfs_init(struct bcm2708_fb *fb)
-+{
-+ static struct debugfs_reg32 stats_registers[] = {
-+ {
-+ "dma_copies",
-+ offsetof(struct bcm2708_fb_stats, dma_copies)
-+ },
-+ {
-+ "dma_irqs",
-+ offsetof(struct bcm2708_fb_stats, dma_irqs)
-+ },
-+ };
-+
-+ fb->debugfs_dir = debugfs_create_dir(DRIVER_NAME, NULL);
-+ if (!fb->debugfs_dir) {
-+ pr_warn("%s: could not create debugfs entry\n",
-+ __func__);
-+ return -EFAULT;
-+ }
-+
-+ fb->stats.regset.regs = stats_registers;
-+ fb->stats.regset.nregs = ARRAY_SIZE(stats_registers);
-+ fb->stats.regset.base = &fb->stats;
-+
-+ if (!debugfs_create_regset32(
-+ "stats", 0444, fb->debugfs_dir, &fb->stats.regset)) {
-+ pr_warn("%s: could not create statistics registers\n",
-+ __func__);
-+ goto fail;
-+ }
-+ return 0;
-+
-+fail:
-+ bcm2708_fb_debugfs_deinit(fb);
-+ return -EFAULT;
-+}
-+
- static int bcm2708_fb_set_bitfields(struct fb_var_screeninfo *var)
- {
- int ret = 0;
-@@ -322,11 +386,148 @@ static void bcm2708_fb_fillrect(struct f
- cfb_fillrect(info, rect);
- }
-
-+/* A helper function for configuring dma control block */
-+static void set_dma_cb(struct bcm2708_dma_cb *cb,
-+ int burst_size,
-+ dma_addr_t dst,
-+ int dst_stride,
-+ dma_addr_t src,
-+ int src_stride,
-+ int w,
-+ int h)
-+{
-+ cb->info = BCM2708_DMA_BURST(burst_size) | BCM2708_DMA_S_WIDTH |
-+ BCM2708_DMA_S_INC | BCM2708_DMA_D_WIDTH |
-+ BCM2708_DMA_D_INC | BCM2708_DMA_TDMODE;
-+ cb->dst = dst;
-+ cb->src = src;
-+ /*
-+ * This is not really obvious from the DMA documentation,
-+ * but the top 16 bits must be programmmed to "height -1"
-+ * and not "height" in 2D mode.
-+ */
-+ cb->length = ((h - 1) << 16) | w;
-+ cb->stride = ((dst_stride - w) << 16) | (u16)(src_stride - w);
-+ cb->pad[0] = 0;
-+ cb->pad[1] = 0;
-+}
-+
- static void bcm2708_fb_copyarea(struct fb_info *info,
- const struct fb_copyarea *region)
- {
-- /*print_debug("bcm2708_fb_copyarea\n"); */
-- cfb_copyarea(info, region);
-+ struct bcm2708_fb *fb = to_bcm2708(info);
-+ struct bcm2708_dma_cb *cb = fb->cb_base;
-+ int bytes_per_pixel = (info->var.bits_per_pixel + 7) >> 3;
-+ /* Channel 0 supports larger bursts and is a bit faster */
-+ int burst_size = (fb->dma_chan == 0) ? 8 : 2;
-+ int pixels = region->width * region->height;
-+
-+ /* Fallback to cfb_copyarea() if we don't like something */
-+ if (bytes_per_pixel > 4 ||
-+ info->var.xres * info->var.yres > 1920 * 1200 ||
-+ region->width <= 0 || region->width > info->var.xres ||
-+ region->height <= 0 || region->height > info->var.yres ||
-+ region->sx < 0 || region->sx >= info->var.xres ||
-+ region->sy < 0 || region->sy >= info->var.yres ||
-+ region->dx < 0 || region->dx >= info->var.xres ||
-+ region->dy < 0 || region->dy >= info->var.yres ||
-+ region->sx + region->width > info->var.xres ||
-+ region->dx + region->width > info->var.xres ||
-+ region->sy + region->height > info->var.yres ||
-+ region->dy + region->height > info->var.yres) {
-+ cfb_copyarea(info, region);
-+ return;
-+ }
-+
-+ if (region->dy == region->sy && region->dx > region->sx) {
-+ /*
-+ * A difficult case of overlapped copy. Because DMA can't
-+ * copy individual scanlines in backwards direction, we need
-+ * two-pass processing. We do it by programming a chain of dma
-+ * control blocks in the first 16K part of the buffer and use
-+ * the remaining 48K as the intermediate temporary scratch
-+ * buffer. The buffer size is sufficient to handle up to
-+ * 1920x1200 resolution at 32bpp pixel depth.
-+ */
-+ int y;
-+ dma_addr_t control_block_pa = fb->cb_handle;
-+ dma_addr_t scratchbuf = fb->cb_handle + 16 * 1024;
-+ int scanline_size = bytes_per_pixel * region->width;
-+ int scanlines_per_cb = (64 * 1024 - 16 * 1024) / scanline_size;
-+
-+ for (y = 0; y < region->height; y += scanlines_per_cb) {
-+ dma_addr_t src =
-+ fb->fb.fix.smem_start +
-+ bytes_per_pixel * region->sx +
-+ (region->sy + y) * fb->fb.fix.line_length;
-+ dma_addr_t dst =
-+ fb->fb.fix.smem_start +
-+ bytes_per_pixel * region->dx +
-+ (region->dy + y) * fb->fb.fix.line_length;
-+
-+ if (region->height - y < scanlines_per_cb)
-+ scanlines_per_cb = region->height - y;
-+
-+ set_dma_cb(cb, burst_size, scratchbuf, scanline_size,
-+ src, fb->fb.fix.line_length,
-+ scanline_size, scanlines_per_cb);
-+ control_block_pa += sizeof(struct bcm2708_dma_cb);
-+ cb->next = control_block_pa;
-+ cb++;
-+
-+ set_dma_cb(cb, burst_size, dst, fb->fb.fix.line_length,
-+ scratchbuf, scanline_size,
-+ scanline_size, scanlines_per_cb);
-+ control_block_pa += sizeof(struct bcm2708_dma_cb);
-+ cb->next = control_block_pa;
-+ cb++;
-+ }
-+ /* move the pointer back to the last dma control block */
-+ cb--;
-+ } else {
-+ /* A single dma control block is enough. */
-+ int sy, dy, stride;
-+ if (region->dy <= region->sy) {
-+ /* processing from top to bottom */
-+ dy = region->dy;
-+ sy = region->sy;
-+ stride = fb->fb.fix.line_length;
-+ } else {
-+ /* processing from bottom to top */
-+ dy = region->dy + region->height - 1;
-+ sy = region->sy + region->height - 1;
-+ stride = -fb->fb.fix.line_length;
-+ }
-+ set_dma_cb(cb, burst_size,
-+ fb->fb.fix.smem_start + dy * fb->fb.fix.line_length +
-+ bytes_per_pixel * region->dx,
-+ stride,
-+ fb->fb.fix.smem_start + sy * fb->fb.fix.line_length +
-+ bytes_per_pixel * region->sx,
-+ stride,
-+ region->width * bytes_per_pixel,
-+ region->height);
-+ }
-+
-+ /* end of dma control blocks chain */
-+ cb->next = 0;
-+
-+
-+ if (pixels < dma_busy_wait_threshold) {
-+ bcm_dma_start(fb->dma_chan_base, fb->cb_handle);
-+ bcm_dma_wait_idle(fb->dma_chan_base);
-+ } else {
-+ void __iomem *dma_chan = fb->dma_chan_base;
-+ cb->info |= BCM2708_DMA_INT_EN;
-+ bcm_dma_start(fb->dma_chan_base, fb->cb_handle);
-+ while (bcm_dma_is_busy(dma_chan)) {
-+ wait_event_interruptible(
-+ fb->dma_waitq,
-+ !bcm_dma_is_busy(dma_chan));
-+ }
-+ fb->stats.dma_irqs++;
-+ }
-+ fb->stats.dma_copies++;
- }
-
- static void bcm2708_fb_imageblit(struct fb_info *info,
-@@ -336,6 +537,24 @@ static void bcm2708_fb_imageblit(struct
- cfb_imageblit(info, image);
- }
-
-+static irqreturn_t bcm2708_fb_dma_irq(int irq, void *cxt)
-+{
-+ struct bcm2708_fb *fb = cxt;
-+
-+ /* FIXME: should read status register to check if this is
-+ * actually interrupting us or not, in case this interrupt
-+ * ever becomes shared amongst several DMA channels
-+ *
-+ * readl(dma_chan_base + BCM2708_DMA_CS) & BCM2708_DMA_IRQ;
-+ */
-+
-+ /* acknowledge the interrupt */
-+ writel(BCM2708_DMA_INT, fb->dma_chan_base + BCM2708_DMA_CS);
-+
-+ wake_up(&fb->dma_waitq);
-+ return IRQ_HANDLED;
-+}
-+
- static struct fb_ops bcm2708_fb_ops = {
- .owner = THIS_MODULE,
- .fb_check_var = bcm2708_fb_check_var,
-@@ -365,7 +584,7 @@ static int bcm2708_fb_register(struct bc
- fb->dma = dma;
- }
- fb->fb.fbops = &bcm2708_fb_ops;
-- fb->fb.flags = FBINFO_FLAG_DEFAULT;
-+ fb->fb.flags = FBINFO_FLAG_DEFAULT | FBINFO_HWACCEL_COPYAREA;
- fb->fb.pseudo_palette = fb->cmap;
-
- strncpy(fb->fb.fix.id, bcm2708_name, sizeof(fb->fb.fix.id));
-@@ -396,6 +615,7 @@ static int bcm2708_fb_register(struct bc
- fb->fb.monspecs.dclkmax = 100000000;
-
- bcm2708_fb_set_bitfields(&fb->fb.var);
-+ init_waitqueue_head(&fb->dma_waitq);
-
- /*
- * Allocate colourmap.
-@@ -421,14 +641,45 @@ static int bcm2708_fb_probe(struct platf
- struct bcm2708_fb *fb;
- int ret;
-
-- fb = kmalloc(sizeof(struct bcm2708_fb), GFP_KERNEL);
-+ fb = kzalloc(sizeof(struct bcm2708_fb), GFP_KERNEL);
- if (!fb) {
- dev_err(&dev->dev,
- "could not allocate new bcm2708_fb struct\n");
- ret = -ENOMEM;
- goto free_region;
- }
-- memset(fb, 0, sizeof(struct bcm2708_fb));
-+
-+ bcm2708_fb_debugfs_init(fb);
-+
-+ fb->cb_base = dma_alloc_writecombine(&dev->dev, SZ_64K,
-+ &fb->cb_handle, GFP_KERNEL);
-+ if (!fb->cb_base) {
-+ dev_err(&dev->dev, "cannot allocate DMA CBs\n");
-+ ret = -ENOMEM;
-+ goto free_fb;
-+ }
-+
-+ pr_info("BCM2708FB: allocated DMA memory %08x\n",
-+ fb->cb_handle);
-+
-+ ret = bcm_dma_chan_alloc(BCM_DMA_FEATURE_BULK,
-+ &fb->dma_chan_base, &fb->dma_irq);
-+ if (ret < 0) {
-+ dev_err(&dev->dev, "couldn't allocate a DMA channel\n");
-+ goto free_cb;
-+ }
-+ fb->dma_chan = ret;
-+
-+ ret = request_irq(fb->dma_irq, bcm2708_fb_dma_irq,
-+ 0, "bcm2708_fb dma", fb);
-+ if (ret) {
-+ pr_err("%s: failed to request DMA irq\n", __func__);
-+ goto free_dma_chan;
-+ }
-+
-+
-+ pr_info("BCM2708FB: allocated DMA channel %d @ %p\n",
-+ fb->dma_chan, fb->dma_chan_base);
-
- fb->dev = dev;
-
-@@ -438,6 +689,11 @@ static int bcm2708_fb_probe(struct platf
- goto out;
- }
-
-+free_dma_chan:
-+ bcm_dma_chan_free(fb->dma_chan);
-+free_cb:
-+ dma_free_writecombine(&dev->dev, SZ_64K, fb->cb_base, fb->cb_handle);
-+free_fb:
- kfree(fb);
- free_region:
- dev_err(&dev->dev, "probe failed, err %d\n", ret);
-@@ -455,8 +711,15 @@ static int bcm2708_fb_remove(struct plat
- iounmap(fb->fb.screen_base);
- unregister_framebuffer(&fb->fb);
-
-+ dma_free_writecombine(&dev->dev, SZ_64K, fb->cb_base, fb->cb_handle);
-+ bcm_dma_chan_free(fb->dma_chan);
-+
- dma_free_coherent(NULL, PAGE_ALIGN(sizeof(*fb->info)), (void *)fb->info,
- fb->dma);
-+ bcm2708_fb_debugfs_deinit(fb);
-+
-+ free_irq(fb->dma_irq, fb);
-+
- kfree(fb);
-
- return 0;
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-03 00:58:30 +0000