From: Alex Deucher <alexander.deucher@amd.com>
Date: Mon, 1 Apr 2013 20:06:25 +0000 (-0400)
Subject: drm/radeon: use frac fb div on RS780/RS880
X-Git-Tag: v3.4.92~44
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=f909046a7bab57744c0498125b8a91450aa12829;p=thirdparty%2Fkernel%2Fstable.git

drm/radeon: use frac fb div on RS780/RS880

commit 411678288d61ba17afe1f8afed92200be6bbc65d upstream.

Monitors seem to prefer it.  Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=37696

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[bwh: Backported to 3.2:
 - Adjust context
 - Add to pll->flags, not radeon_crtc->pll_flags]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
index 77dc799215a5e..dc612efbeb7a4 100644
--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -573,6 +573,9 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc,
 		/* use frac fb div on APUs */
 		if (ASIC_IS_DCE41(rdev) || ASIC_IS_DCE61(rdev))
 			pll->flags |= RADEON_PLL_USE_FRAC_FB_DIV;
+		/* use frac fb div on RS780/RS880 */
+		if ((rdev->family == CHIP_RS780) || (rdev->family == CHIP_RS880))
+			pll->flags |= RADEON_PLL_USE_FRAC_FB_DIV;
 		if (ASIC_IS_DCE32(rdev) && mode->clock > 165000)
 			pll->flags |= RADEON_PLL_USE_FRAC_FB_DIV;
 	} else {