[137/272] atyfb: Fix bootup hangs on sparc64.

From: Greg KH
Date: Tue Feb 15 2011 - 20:28:45 EST


2.6.37-stable review patch. If anyone has any objections, please let us know.

------------------

From: David S. Miller <davem@xxxxxxxxxxxxx>

[ Upstream commit 09798eb9479da3413bdf96e7d22a84d8b21e05e1 ]

After commit 25edd6946a1d74e5e77813c2324a0908c68bcf9e ("sparc64: Get
rid of indirect p1275 PROM call buffer.") we can't pass virtual
addresses >4GB to PROM calls.

Largely this is never necessary in drivers because we have a copy of
the entire PROM device tree in the kernel and a set of of_*()
interfaces to access it.

Unfortunately there were some lingering prom calls in the atyfb
driver, in particular prom_finddevice() was being called with an
on-stack address which could be anywhere.

This code is actually probing for information we already have, the
PROM choosen console output device is stored in of_console_device so
all of this nasty code consolidates into a one-line comparison.

Next we have some prom_getintdefault() calls which are trivially
transformed into the equivalent of_getintprop_default().

Special thanks to Fabio, who figured out exactly where the bootup
was hanging. That made this bug trivial to fix.

Reported-by: Fabio M. Di NItto <fabbione@xxxxxxxxxxxx>
Reported-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Reported-by: Frans van Berckel <fberckel@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Fabio M. Di NItto <fabbione@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/video/aty/atyfb_base.c | 27 +++++----------------------
1 file changed, 5 insertions(+), 22 deletions(-)

--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -2969,10 +2969,8 @@ static int __devinit atyfb_setup_sparc(s
{
struct atyfb_par *par = info->par;
struct device_node *dp;
- char prop[128];
- phandle node;
- int len, i, j, ret;
u32 mem, chip_id;
+ int i, j, ret;

/*
* Map memory-mapped registers.
@@ -3088,23 +3086,8 @@ static int __devinit atyfb_setup_sparc(s
aty_st_le32(MEM_CNTL, mem, par);
}

- /*
- * If this is the console device, we will set default video
- * settings to what the PROM left us with.
- */
- node = prom_getchild(prom_root_node);
- node = prom_searchsiblings(node, "aliases");
- if (node) {
- len = prom_getproperty(node, "screen", prop, sizeof(prop));
- if (len > 0) {
- prop[len] = '\0';
- node = prom_finddevice(prop);
- } else
- node = 0;
- }
-
dp = pci_device_to_OF_node(pdev);
- if (node == dp->phandle) {
+ if (dp == of_console_device) {
struct fb_var_screeninfo *var = &default_var;
unsigned int N, P, Q, M, T, R;
u32 v_total, h_total;
@@ -3112,9 +3095,9 @@ static int __devinit atyfb_setup_sparc(s
u8 pll_regs[16];
u8 clock_cntl;

- crtc.vxres = prom_getintdefault(node, "width", 1024);
- crtc.vyres = prom_getintdefault(node, "height", 768);
- var->bits_per_pixel = prom_getintdefault(node, "depth", 8);
+ crtc.vxres = of_getintprop_default(dp, "width", 1024);
+ crtc.vyres = of_getintprop_default(dp, "height", 768);
+ var->bits_per_pixel = of_getintprop_default(dp, "depth", 8);
var->xoffset = var->yoffset = 0;
crtc.h_tot_disp = aty_ld_le32(CRTC_H_TOTAL_DISP, par);
crtc.h_sync_strt_wid = aty_ld_le32(CRTC_H_SYNC_STRT_WID, par);


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