[PATCH 1/4] [resend] tridentfb: fix hang on Blade3D with CONFIG_CC_OPTIMIZE_FOR_SIZE

From: Ondrej Zary
Date: Tue Mar 03 2015 - 15:56:35 EST

When the kernel is compiled with -Os (CONFIG_CC_OPTIMIZE_FOR_SIZE), tridentfb
hangs the machine upon load with Blade3D cards unless acceleration is disabled.

This is caused by memcpy() which copies data byte-by-byte (rep movsb) when
compiled with -Os. The card does not like that - it requires 32-bit access.

Use iowrite_32() instead.

Signed-off-by: Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Krzysztof Helt <krzysztof.h1@xxxxx>
drivers/video/fbdev/tridentfb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/tridentfb.c b/drivers/video/fbdev/tridentfb.c
index 7ed9a22..7429713 100644
--- a/drivers/video/fbdev/tridentfb.c
+++ b/drivers/video/fbdev/tridentfb.c
@@ -226,7 +226,7 @@ static void blade_image_blit(struct tridentfb_par *par, const char *data,
writemmr(par, DST1, point(x, y));
writemmr(par, DST2, point(x + w - 1, y + h - 1));

- memcpy(par->io_virt + 0x10000, data, 4 * size);
+ iowrite32_rep(par->io_virt + 0x10000, data, size);

static void blade_copy_rect(struct tridentfb_par *par,
Ondrej Zary

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