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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-22 13:08:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-22 13:08:22 -0700
commitbe53bfdb8088e9d1924199cc1a96e113756b1075 (patch)
tree8c65eb9d82ca4c0f11c17cfdc44d5263820b415b /drivers/gpu/drm/udl/udl_transfer.c
parentb2094ef840697bc8ca5d17a83b7e30fad5f1e9fa (diff)
parent5466c7b1683a23dbbcfb7ee4a71c4f23886001c7 (diff)
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Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm main changes from Dave Airlie: "This is the main drm pull request, I'm probably going to send two more smaller ones, will explain below. This contains a patch that is also in the fbdev tree, but it should be the same patch, it added an API for hot unplugging framebuffer devices, and I need that API for a new driver. It also contains some changes to the i2c tree which Jean has acked, and one change to moorestown platform stuff in x86. Highlights: - new drivers: UDL driver for USB displaylink devices, kms only, should support correct hotplug operations. - core: i2c speedups + better hotplug support, EDID overriding via firmware interface - allows user to load a firmware for a broken monitor/kvm from userspace, it even has documentation for it. - exynos: new HDMI audio + hdmi 1.4 + virtual output driver - gma500: code cleanup - radeon: cleanups, CS optimisations, streamout support and pageflip fix - nouveau: NVD9 displayport support + more reclocking work - i915: re-enabling GMBUS, finish gpu patch (might help hibernation who knows), missed irq fixes, stencil tiling fixes, interlaced support, aliasesd PPGTT support for SNB/IVB, swizzling for SNB/IVB, semaphore fixes As well as the usual bunch of cleanups and fixes all over the place. I've got two things I'd like to merge a bit later: a) AMD support for all their new radeonhd 7000 series GPU and APUs. AMD dropped this a bit late due to insane internal review processes, (please AMD just follow Intel and let open source guys ship stuff early) however I don't want to penalise people who own this hardware (since its been on sale for 3-4 months and GPU hw doesn't exactly have a lifetime in years) and consign them to using closed drivers for longer than necessary. The changes are well contained and just plug into the driver new gpu functionality so they should be fairly regression proof. I just want to give them a bit of a run on the hw AMD kindly sent me. b) drm prime/dma-buf interface code. This is just infrastructure code to expose the dma-buf stuff to drm drivers and to userspace. I'm not planning on pushing any driver support in this cycle (except maybe exynos), but I'd like to get the infrastructure code in so for the next cycle I can start getting the driver support into the individual drivers. We have started driver support for i915, nouveau and udl along with I think exynos and omap in staging. However this code relies on the dma-buf tree being pulled into your tree first since it needs the latest interfaces from that tree. I'll push to get that tree sent asap. (oh and any warnings you see in i915 are gcc's fault from what anyone can see)." Fix up trivial conflicts in arch/x86/platform/mrst/mrst.c due to the new msic_thermal_platform_data() thermal function being added next to the tc35876x_platform_data() i2c device function.. * 'drm-next' of git://people.freedesktop.org/~airlied/linux: (326 commits) drm/i915: use DDC_ADDR instead of hard-coding it drm/radeon: use DDC_ADDR instead of hard-coding it drm: remove unneeded redefinition of DDC_ADDR drm/exynos: added virtual display driver. drm: allow loading an EDID as firmware to override broken monitor drm/exynos: enable hdmi audio feature drm/exynos: add default pixel format for plane drm/exynos: cleanup exynos_hdmi.h drm/exynos: add is_local member in exynos_drm_subdrv struct drm/exynos: add subdrv open/close functions drm/exynos: remove module of exynos drm subdrv drm/exynos: release pending pageflip events when closed drm/exynos: added new funtion to get/put dma address. drm/exynos: update gem and buffer framework. drm/exynos: added mode_fixup feature and code clean. drm/exynos: add HDMI version 1.4 support drm/exynos: remove exynos_mixer.h gma500: Fix mmap frambuffer drm/radeon: Drop radeon_gem_object_(un)pin. drm/radeon: Restrict offset for legacy display engine. ...
Diffstat (limited to 'drivers/gpu/drm/udl/udl_transfer.c')
-rw-r--r--drivers/gpu/drm/udl/udl_transfer.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/gpu/drm/udl/udl_transfer.c b/drivers/gpu/drm/udl/udl_transfer.c
new file mode 100644
index 000000000000..b9320e2608dd
--- /dev/null
+++ b/drivers/gpu/drm/udl/udl_transfer.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright (C) 2012 Red Hat
+ * based in parts on udlfb.c:
+ * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
+ * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
+ * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License v2. See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fb.h>
+#include <linux/prefetch.h>
+
+#include "drmP.h"
+#include "udl_drv.h"
+
+#define MAX_CMD_PIXELS 255
+
+#define RLX_HEADER_BYTES 7
+#define MIN_RLX_PIX_BYTES 4
+#define MIN_RLX_CMD_BYTES (RLX_HEADER_BYTES + MIN_RLX_PIX_BYTES)
+
+#define RLE_HEADER_BYTES 6
+#define MIN_RLE_PIX_BYTES 3
+#define MIN_RLE_CMD_BYTES (RLE_HEADER_BYTES + MIN_RLE_PIX_BYTES)
+
+#define RAW_HEADER_BYTES 6
+#define MIN_RAW_PIX_BYTES 2
+#define MIN_RAW_CMD_BYTES (RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
+
+/*
+ * Trims identical data from front and back of line
+ * Sets new front buffer address and width
+ * And returns byte count of identical pixels
+ * Assumes CPU natural alignment (unsigned long)
+ * for back and front buffer ptrs and width
+ */
+#if 0
+static int udl_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
+{
+ int j, k;
+ const unsigned long *back = (const unsigned long *) bback;
+ const unsigned long *front = (const unsigned long *) *bfront;
+ const int width = *width_bytes / sizeof(unsigned long);
+ int identical = width;
+ int start = width;
+ int end = width;
+
+ prefetch((void *) front);
+ prefetch((void *) back);
+
+ for (j = 0; j < width; j++) {
+ if (back[j] != front[j]) {
+ start = j;
+ break;
+ }
+ }
+
+ for (k = width - 1; k > j; k--) {
+ if (back[k] != front[k]) {
+ end = k+1;
+ break;
+ }
+ }
+
+ identical = start + (width - end);
+ *bfront = (u8 *) &front[start];
+ *width_bytes = (end - start) * sizeof(unsigned long);
+
+ return identical * sizeof(unsigned long);
+}
+#endif
+
+static inline u16 pixel32_to_be16p(const uint8_t *pixel)
+{
+ uint32_t pix = *(uint32_t *)pixel;
+ u16 retval;
+
+ retval = (((pix >> 3) & 0x001f) |
+ ((pix >> 5) & 0x07e0) |
+ ((pix >> 8) & 0xf800));
+ return retval;
+}
+
+/*
+ * Render a command stream for an encoded horizontal line segment of pixels.
+ *
+ * A command buffer holds several commands.
+ * It always begins with a fresh command header
+ * (the protocol doesn't require this, but we enforce it to allow
+ * multiple buffers to be potentially encoded and sent in parallel).
+ * A single command encodes one contiguous horizontal line of pixels
+ *
+ * The function relies on the client to do all allocation, so that
+ * rendering can be done directly to output buffers (e.g. USB URBs).
+ * The function fills the supplied command buffer, providing information
+ * on where it left off, so the client may call in again with additional
+ * buffers if the line will take several buffers to complete.
+ *
+ * A single command can transmit a maximum of 256 pixels,
+ * regardless of the compression ratio (protocol design limit).
+ * To the hardware, 0 for a size byte means 256
+ *
+ * Rather than 256 pixel commands which are either rl or raw encoded,
+ * the rlx command simply assumes alternating raw and rl spans within one cmd.
+ * This has a slightly larger header overhead, but produces more even results.
+ * It also processes all data (read and write) in a single pass.
+ * Performance benchmarks of common cases show it having just slightly better
+ * compression than 256 pixel raw or rle commands, with similar CPU consumpion.
+ * But for very rl friendly data, will compress not quite as well.
+ */
+static void udl_compress_hline16(
+ const u8 **pixel_start_ptr,
+ const u8 *const pixel_end,
+ uint32_t *device_address_ptr,
+ uint8_t **command_buffer_ptr,
+ const uint8_t *const cmd_buffer_end, int bpp)
+{
+ const u8 *pixel = *pixel_start_ptr;
+ uint32_t dev_addr = *device_address_ptr;
+ uint8_t *cmd = *command_buffer_ptr;
+
+ while ((pixel_end > pixel) &&
+ (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {
+ uint8_t *raw_pixels_count_byte = 0;
+ uint8_t *cmd_pixels_count_byte = 0;
+ const u8 *raw_pixel_start = 0;
+ const u8 *cmd_pixel_start, *cmd_pixel_end = 0;
+
+ prefetchw((void *) cmd); /* pull in one cache line at least */
+
+ *cmd++ = 0xaf;
+ *cmd++ = 0x6b;
+ *cmd++ = (uint8_t) ((dev_addr >> 16) & 0xFF);
+ *cmd++ = (uint8_t) ((dev_addr >> 8) & 0xFF);
+ *cmd++ = (uint8_t) ((dev_addr) & 0xFF);
+
+ cmd_pixels_count_byte = cmd++; /* we'll know this later */
+ cmd_pixel_start = pixel;
+
+ raw_pixels_count_byte = cmd++; /* we'll know this later */
+ raw_pixel_start = pixel;
+
+ cmd_pixel_end = pixel + (min(MAX_CMD_PIXELS + 1,
+ min((int)(pixel_end - pixel) / bpp,
+ (int)(cmd_buffer_end - cmd) / 2))) * bpp;
+
+ prefetch_range((void *) pixel, (cmd_pixel_end - pixel) * bpp);
+
+ while (pixel < cmd_pixel_end) {
+ const u8 * const repeating_pixel = pixel;
+
+ if (bpp == 2)
+ *(uint16_t *)cmd = cpu_to_be16p((uint16_t *)pixel);
+ else if (bpp == 4)
+ *(uint16_t *)cmd = cpu_to_be16(pixel32_to_be16p(pixel));
+
+ cmd += 2;
+ pixel += bpp;
+
+ if (unlikely((pixel < cmd_pixel_end) &&
+ (!memcmp(pixel, repeating_pixel, bpp)))) {
+ /* go back and fill in raw pixel count */
+ *raw_pixels_count_byte = (((repeating_pixel -
+ raw_pixel_start) / bpp) + 1) & 0xFF;
+
+ while ((pixel < cmd_pixel_end)
+ && (!memcmp(pixel, repeating_pixel, bpp))) {
+ pixel += bpp;
+ }
+
+ /* immediately after raw data is repeat byte */
+ *cmd++ = (((pixel - repeating_pixel) / bpp) - 1) & 0xFF;
+
+ /* Then start another raw pixel span */
+ raw_pixel_start = pixel;
+ raw_pixels_count_byte = cmd++;
+ }
+ }
+
+ if (pixel > raw_pixel_start) {
+ /* finalize last RAW span */
+ *raw_pixels_count_byte = ((pixel-raw_pixel_start) / bpp) & 0xFF;
+ }
+
+ *cmd_pixels_count_byte = ((pixel - cmd_pixel_start) / bpp) & 0xFF;
+ dev_addr += ((pixel - cmd_pixel_start) / bpp) * 2;
+ }
+
+ if (cmd_buffer_end <= MIN_RLX_CMD_BYTES + cmd) {
+ /* Fill leftover bytes with no-ops */
+ if (cmd_buffer_end > cmd)
+ memset(cmd, 0xAF, cmd_buffer_end - cmd);
+ cmd = (uint8_t *) cmd_buffer_end;
+ }
+
+ *command_buffer_ptr = cmd;
+ *pixel_start_ptr = pixel;
+ *device_address_ptr = dev_addr;
+
+ return;
+}
+
+/*
+ * There are 3 copies of every pixel: The front buffer that the fbdev
+ * client renders to, the actual framebuffer across the USB bus in hardware
+ * (that we can only write to, slowly, and can never read), and (optionally)
+ * our shadow copy that tracks what's been sent to that hardware buffer.
+ */
+int udl_render_hline(struct drm_device *dev, int bpp, struct urb **urb_ptr,
+ const char *front, char **urb_buf_ptr,
+ u32 byte_offset, u32 byte_width,
+ int *ident_ptr, int *sent_ptr)
+{
+ const u8 *line_start, *line_end, *next_pixel;
+ u32 base16 = 0 + (byte_offset / bpp) * 2;
+ struct urb *urb = *urb_ptr;
+ u8 *cmd = *urb_buf_ptr;
+ u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;
+
+ line_start = (u8 *) (front + byte_offset);
+ next_pixel = line_start;
+ line_end = next_pixel + byte_width;
+
+ while (next_pixel < line_end) {
+
+ udl_compress_hline16(&next_pixel,
+ line_end, &base16,
+ (u8 **) &cmd, (u8 *) cmd_end, bpp);
+
+ if (cmd >= cmd_end) {
+ int len = cmd - (u8 *) urb->transfer_buffer;
+ if (udl_submit_urb(dev, urb, len))
+ return 1; /* lost pixels is set */
+ *sent_ptr += len;
+ urb = udl_get_urb(dev);
+ if (!urb)
+ return 1; /* lost_pixels is set */
+ *urb_ptr = urb;
+ cmd = urb->transfer_buffer;
+ cmd_end = &cmd[urb->transfer_buffer_length];
+ }
+ }
+
+ *urb_buf_ptr = cmd;
+
+ return 0;
+}
+