mirror of https://github.com/hak5/openwrt-owl.git
168 lines
4.8 KiB
Diff
168 lines
4.8 KiB
Diff
From 26a7e2d3d11c23acc6f87414da736c07a3b9cc52 Mon Sep 17 00:00:00 2001
|
|
From: popcornmix <popcornmix@gmail.com>
|
|
Date: Sat, 5 Nov 2016 14:14:43 +0000
|
|
Subject: [PATCH] bcm2708_fb: Add ioctl for reading gpu memory through dma
|
|
|
|
---
|
|
drivers/video/fbdev/bcm2708_fb.c | 109 +++++++++++++++++++++++++++++++++++++++
|
|
include/uapi/linux/fb.h | 7 +++
|
|
2 files changed, 116 insertions(+)
|
|
|
|
--- a/drivers/video/fbdev/bcm2708_fb.c
|
|
+++ b/drivers/video/fbdev/bcm2708_fb.c
|
|
@@ -31,8 +31,10 @@
|
|
#include <linux/console.h>
|
|
#include <linux/debugfs.h>
|
|
#include <asm/sizes.h>
|
|
+#include <asm/uaccess.h>
|
|
#include <linux/io.h>
|
|
#include <linux/dma-mapping.h>
|
|
+#include <linux/cred.h>
|
|
#include <soc/bcm2835/raspberrypi-firmware.h>
|
|
|
|
//#define BCM2708_FB_DEBUG
|
|
@@ -429,6 +431,110 @@ static int bcm2708_fb_pan_display(struct
|
|
return result;
|
|
}
|
|
|
|
+static void dma_memcpy(struct bcm2708_fb *fb, dma_addr_t dst, dma_addr_t src, int size)
|
|
+{
|
|
+ int burst_size = (fb->dma_chan == 0) ? 8 : 2;
|
|
+ struct bcm2708_dma_cb *cb = fb->cb_base;
|
|
+
|
|
+ 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;
|
|
+ cb->length = size;
|
|
+ cb->stride = 0;
|
|
+ cb->pad[0] = 0;
|
|
+ cb->pad[1] = 0;
|
|
+ cb->next = 0;
|
|
+
|
|
+ if (size < 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++;
|
|
+}
|
|
+
|
|
+#define INTALIAS_NORMAL(x) ((x)&~0xc0000000) // address with no aliases
|
|
+#define INTALIAS_L1L2_NONALLOCATING(x) (((x)&~0xc0000000)|0x80000000) // cache coherent but non-allocating in L1 and L2
|
|
+
|
|
+static long vc_mem_copy(struct bcm2708_fb *fb, unsigned long arg)
|
|
+{
|
|
+ struct fb_dmacopy ioparam;
|
|
+ size_t size = PAGE_SIZE;
|
|
+ u32 *buf = NULL;
|
|
+ dma_addr_t bus_addr;
|
|
+ long rc = 0;
|
|
+ size_t offset;
|
|
+ struct { u32 base, length; } gpu = {};
|
|
+
|
|
+ /* restrict this to root user */
|
|
+ if (!uid_eq(current_euid(), GLOBAL_ROOT_UID))
|
|
+ {
|
|
+ rc = -EFAULT;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ /* Get the parameter data.
|
|
+ */
|
|
+ if (copy_from_user
|
|
+ (&ioparam, (void *)arg, sizeof(ioparam)) != 0) {
|
|
+ pr_err("[%s]: failed to copy-from-user\n",
|
|
+ __func__);
|
|
+ rc = -EFAULT;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ rc = rpi_firmware_property(fb->fw,
|
|
+ RPI_FIRMWARE_GET_VC_MEMORY,
|
|
+ &gpu, sizeof(gpu));
|
|
+ if (rc != 0 || gpu.base == 0 || gpu.length == 0) {
|
|
+ pr_err("[%s]: Unable to determine gpu memory %ld,%x,%x)\n", __func__, rc, gpu.base, gpu.length);
|
|
+ return -EFAULT;
|
|
+ }
|
|
+
|
|
+ if (INTALIAS_NORMAL(ioparam.src) < gpu.base || INTALIAS_NORMAL(ioparam.src) >= gpu.base + gpu.length) {
|
|
+ pr_err("[%s]: Invalid memory access %x (%x-%x)", __func__, INTALIAS_NORMAL(ioparam.src), gpu.base, gpu.base + gpu.length);
|
|
+ return -EFAULT;
|
|
+ }
|
|
+
|
|
+ buf = dma_alloc_coherent(NULL, PAGE_ALIGN(size), &bus_addr,
|
|
+ GFP_ATOMIC);
|
|
+ if (!buf) {
|
|
+ pr_err("[%s]: failed to dma_alloc_coherent(%d)\n",
|
|
+ __func__, size);
|
|
+ rc = -ENOMEM;
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ for (offset = 0; offset < ioparam.length; offset += size) {
|
|
+ size_t remaining = ioparam.length - offset;
|
|
+ size_t s = min(size, remaining);
|
|
+ unsigned char *p = (unsigned char *)ioparam.src + offset;
|
|
+ unsigned char *q = (unsigned char *)ioparam.dst + offset;
|
|
+ dma_memcpy(fb, (dma_addr_t)buf, INTALIAS_L1L2_NONALLOCATING((dma_addr_t)p), size);
|
|
+ if (copy_to_user(q, buf, s) != 0) {
|
|
+ pr_err("[%s]: failed to copy-to-user\n",
|
|
+ __func__);
|
|
+ rc = -EFAULT;
|
|
+ goto out;
|
|
+ }
|
|
+ }
|
|
+out:
|
|
+ if (buf)
|
|
+ dma_free_coherent(NULL, PAGE_ALIGN(size), buf, bus_addr);
|
|
+ return rc;
|
|
+}
|
|
+
|
|
static int bcm2708_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct bcm2708_fb *fb = to_bcm2708(info);
|
|
@@ -441,6 +547,9 @@ static int bcm2708_ioctl(struct fb_info
|
|
RPI_FIRMWARE_FRAMEBUFFER_SET_VSYNC,
|
|
&dummy, sizeof(dummy));
|
|
break;
|
|
+ case FBIODMACOPY:
|
|
+ ret = vc_mem_copy(fb, arg);
|
|
+ break;
|
|
default:
|
|
dev_dbg(info->device, "Unknown ioctl 0x%x\n", cmd);
|
|
return -ENOTTY;
|
|
--- a/include/uapi/linux/fb.h
|
|
+++ b/include/uapi/linux/fb.h
|
|
@@ -39,6 +39,7 @@
|
|
* be concurrently added to the mainline kernel
|
|
*/
|
|
#define FBIOCOPYAREA _IOW('z', 0x21, struct fb_copyarea)
|
|
+#define FBIODMACOPY _IOW('z', 0x22, struct fb_dmacopy)
|
|
|
|
#define FB_TYPE_PACKED_PIXELS 0 /* Packed Pixels */
|
|
#define FB_TYPE_PLANES 1 /* Non interleaved planes */
|
|
@@ -351,6 +352,12 @@ struct fb_copyarea {
|
|
__u32 sy;
|
|
};
|
|
|
|
+struct fb_dmacopy {
|
|
+ dma_addr_t dst;
|
|
+ dma_addr_t src;
|
|
+ __u32 length;
|
|
+};
|
|
+
|
|
struct fb_fillrect {
|
|
__u32 dx; /* screen-relative */
|
|
__u32 dy;
|