From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch improves reliability of suspend/resume by making sure AGP is
disabled on the Rage 128 chip before putting it into a suspend state. It
works in conjunction with the uninorth-agp suspend patch, but should be
harmless on machines with a different AGP bridge.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/video/aty/aty128fb.c | 22 ++++++++++++++++++++++
1 files changed, 22 insertions(+)
diff -puN drivers/video/aty/aty128fb.c~aty128fb-disable-agp-on-suspend drivers/video/aty/aty128fb.c
--- 25/drivers/video/aty/aty128fb.c~aty128fb-disable-agp-on-suspend 2005-02-28 20:32:24.000000000 -0800
+++ 25-akpm/drivers/video/aty/aty128fb.c 2005-02-28 20:32:24.000000000 -0800
@@ -2334,6 +2334,7 @@ static int aty128_pci_suspend(struct pci
{
struct fb_info *info = pci_get_drvdata(pdev);
struct aty128fb_par *par = info->par;
+ u8 agp;
/* We don't do anything but D2, for now we return 0, but
* we may want to change that. How do we know if the BIOS
@@ -2371,6 +2372,27 @@ static int aty128_pci_suspend(struct pci
par->asleep = 1;
par->lock_blank = 1;
+ /* Disable AGP. The AGP host should have done it, but since ordering
+ * isn't always properly guaranteed in this specific case, let's make
+ * sure it's disabled on card side now. Ultimately, when merging fbdev
+ * and dri into some common infrastructure, this will be handled
+ * more nicely. The host bridge side will (or will not) be dealt with
+ * by the bridge AGP driver, we don't attempt to touch it here.
+ */
+ agp = pci_find_capability(pdev, PCI_CAP_ID_AGP);
+ if (agp) {
+ u32 cmd;
+
+ pci_read_config_dword(pdev, agp + PCI_AGP_COMMAND, &cmd);
+ if (cmd & PCI_AGP_COMMAND_AGP) {
+ printk(KERN_INFO "aty128fb: AGP was enabled, "
+ "disabling ...\n");
+ cmd &= ~PCI_AGP_COMMAND_AGP;
+ pci_write_config_dword(pdev, agp + PCI_AGP_COMMAND,
+ cmd);
+ }
+ }
+
/* We need a way to make sure the fbdev layer will _not_ touch the
* framebuffer before we put the chip to suspend state. On 2.4, I
* used dummy fb ops, 2.5 need proper support for this at the
_