Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755878Ab3HPWhU (ORCPT ); Fri, 16 Aug 2013 18:37:20 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:51417 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754466Ab3HPWhQ (ORCPT ); Fri, 16 Aug 2013 18:37:16 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Daniel Vetter , Haitao Zhang , Kamal Mostafa Subject: [PATCH 080/133] drm/i915: Make data/link N value power of two Date: Fri, 16 Aug 2013 15:33:42 -0700 Message-Id: <1376692475-28413-81-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1376692475-28413-1-git-send-email-kamal@canonical.com> References: <1376692475-28413-1-git-send-email-kamal@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4417 Lines: 127 3.8.13.7 -stable review patch. If anyone has any objections, please let me know. ------------------ From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= commit a65851af59387146a28a928c3e7bb17dabc5db72 upstream. The BIOS uses power of two values for the data/link N value. Follow suit to make the Zotac DP to dual-HDMI dongle work. v2: Clean up the magic numbers and defines Change the N clamping to be a bit easier on the eye Rename intel_reduce_ratio to intel_reduce_m_n_ratio Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49402 Signed-off-by: Ville Syrjälä Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59810 Tested-by: Jesse Barnes Signed-off-by: Daniel Vetter [Haitao Zhang: backport to 3.8] Signed-off-by: Haitao Zhang Signed-off-by: Kamal Mostafa --- drivers/gpu/drm/i915/i915_reg.h | 12 ++++-------- drivers/gpu/drm/i915/intel_display.c | 23 +++++++++++++++-------- 2 files changed, 19 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b7315e3..24f0368 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -2602,14 +2602,14 @@ #define _PIPEB_GMCH_DATA_M 0x71050 /* Transfer unit size for display port - 1, default is 0x3f (for TU size 64) */ -#define PIPE_GMCH_DATA_M_TU_SIZE_MASK (0x3f << 25) -#define PIPE_GMCH_DATA_M_TU_SIZE_SHIFT 25 +#define TU_SIZE(x) (((x)-1) << 25) /* default size 64 */ +#define TU_SIZE_MASK (0x3f << 25) -#define PIPE_GMCH_DATA_M_MASK (0xffffff) +#define DATA_LINK_M_N_MASK (0xffffff) +#define DATA_LINK_N_MAX (0x800000) #define _PIPEA_GMCH_DATA_N 0x70054 #define _PIPEB_GMCH_DATA_N 0x71054 -#define PIPE_GMCH_DATA_N_MASK (0xffffff) /* * Computing Link M and N values for the Display Port link @@ -2624,11 +2624,9 @@ #define _PIPEA_DP_LINK_M 0x70060 #define _PIPEB_DP_LINK_M 0x71060 -#define PIPEA_DP_LINK_M_MASK (0xffffff) #define _PIPEA_DP_LINK_N 0x70064 #define _PIPEB_DP_LINK_N 0x71064 -#define PIPEA_DP_LINK_N_MASK (0xffffff) #define PIPE_GMCH_DATA_M(pipe) _PIPE(pipe, _PIPEA_GMCH_DATA_M, _PIPEB_GMCH_DATA_M) #define PIPE_GMCH_DATA_N(pipe) _PIPE(pipe, _PIPEA_GMCH_DATA_N, _PIPEB_GMCH_DATA_N) @@ -3294,8 +3292,6 @@ #define _PIPEA_DATA_M1 0x60030 -#define TU_SIZE(x) (((x)-1) << 25) /* default size 64 */ -#define TU_SIZE_MASK 0x7e000000 #define PIPE_DATA_M1_OFFSET 0 #define _PIPEA_DATA_N1 0x60034 #define PIPE_DATA_N1_OFFSET 0 diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index e094040..1f20ac5 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4042,26 +4042,33 @@ struct fdi_m_n { static void fdi_reduce_ratio(u32 *num, u32 *den) { - while (*num > 0xffffff || *den > 0xffffff) { + while (*num > DATA_LINK_M_N_MASK || + *den > DATA_LINK_M_N_MASK) { *num >>= 1; *den >>= 1; } } +static void compute_m_n(unsigned int m, unsigned int n, + uint32_t *ret_m, uint32_t *ret_n) +{ + *ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX); + *ret_m = div_u64((uint64_t) m * *ret_n, n); + fdi_reduce_ratio(ret_m, ret_n); +} + static void ironlake_compute_m_n(int bits_per_pixel, int nlanes, int pixel_clock, int link_clock, struct fdi_m_n *m_n) { m_n->tu = 64; /* default size */ - /* BUG_ON(pixel_clock > INT_MAX / 36); */ - m_n->gmch_m = bits_per_pixel * pixel_clock; - m_n->gmch_n = link_clock * nlanes * 8; - fdi_reduce_ratio(&m_n->gmch_m, &m_n->gmch_n); + compute_m_n(bits_per_pixel * pixel_clock, + link_clock * nlanes * 8, + &m_n->gmch_m, &m_n->gmch_n); - m_n->link_m = pixel_clock; - m_n->link_n = link_clock; - fdi_reduce_ratio(&m_n->link_m, &m_n->link_n); + compute_m_n(pixel_clock, link_clock, + &m_n->link_m, &m_n->link_n); } static inline bool intel_panel_use_ssc(struct drm_i915_private *dev_priv) -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/