bcm2708_fb: Avoid firmware mbox call in vc_mem_copy

If firmware has locked up it is useful to get vcdbg log out without a firmware mbox response.
Issue the mbox call at probe time instead.

Signed-off-by: popcornmix <popcornmix@gmail.com>

diff --git a/drivers/video/fbdev/bcm2708_fb.c b/drivers/video/fbdev/bcm2708_fb.c
index 53c5a0bdadb4be9251affdabed66305842a08e72..612293cf9f1bd93ad2f2aefdd7ca0f5eb2a412f0 100644 (file)
--- a/drivers/video/fbdev/bcm2708_fb.c
+++ b/drivers/video/fbdev/bcm2708_fb.c
@@ -96,6 +96,7 @@ struct bcm2708_fb {
        wait_queue_head_t dma_waitq;
        struct bcm2708_fb_stats stats;
        unsigned long fb_bus_address;
+       struct { u32 base, length; } gpu;
 };
 
 #define to_bcm2708(info)       container_of(info, struct bcm2708_fb, fb)
@@ -472,7 +473,6 @@ static long vc_mem_copy(struct bcm2708_fb *fb, unsigned long arg)
        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))
@@ -491,16 +491,13 @@ static long vc_mem_copy(struct bcm2708_fb *fb, unsigned long arg)
                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);
+       if (fb->gpu.base == 0 || fb->gpu.length == 0) {
+               pr_err("[%s]: Unable to determine gpu memory (%x,%x)\n", __func__, fb->gpu.base, fb->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);
+       if (INTALIAS_NORMAL(ioparam.src) < fb->gpu.base || INTALIAS_NORMAL(ioparam.src) >= fb->gpu.base + fb->gpu.length) {
+               pr_err("[%s]: Invalid memory access %x (%x-%x)", __func__, INTALIAS_NORMAL(ioparam.src), fb->gpu.base, fb->gpu.base + fb->gpu.length);
                return -EFAULT;
        }
 
@@ -869,6 +866,11 @@ static int bcm2708_fb_probe(struct platform_device *dev)
        fb->dev = dev;
        fb->fb.device = &dev->dev;
 
+       // failure here isn't fatal, but we'll fail in vc_mem_copy if fb->gpu is not valid
+       rpi_firmware_property(fb->fw,
+                                   RPI_FIRMWARE_GET_VC_MEMORY,
+                                   &fb->gpu, sizeof(fb->gpu));
+
        ret = bcm2708_fb_register(fb);
        if (ret == 0) {
                platform_set_drvdata(dev, fb);