viafb: try to map less memory in case of failure

The current code might result in trying to remap 512MB video ram on
a 32 bit system which is quite likely to fail.
This patch tries to map less of it down to 8MB as this should still
be enough to get a reasonably well working framebuffer. This should
make viafb work for many people without requiring them to manually
allocate more space.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/video/via/via-core.c b/drivers/video/via/via-core.c
index 5b0129b42d8a..eb112b621735 100644
--- a/drivers/video/via/via-core.c
+++ b/drivers/video/via/via-core.c
@@ -505,7 +505,14 @@ static int __devinit via_pci_setup_mmio(struct viafb_dev *vdev)
         ret = vdev->fbmem_len = viafb_get_fb_size_from_pci(vdev->chip_type);
         if (ret < 0)
                 goto out_unmap;
-        vdev->fbmem = ioremap_wc(vdev->fbmem_start, vdev->fbmem_len);
+
+        /* try to map less memory on failure, 8 MB should be still enough */
+        for (; vdev->fbmem_len >= 8 << 20; vdev->fbmem_len /= 2) {
+                vdev->fbmem = ioremap_wc(vdev->fbmem_start, vdev->fbmem_len);
+                if (vdev->fbmem)
+                        break;
+        }
+
         if (vdev->fbmem == NULL) {
                 ret = -ENOMEM;
                 goto out_unmap;