From: Daniel Vetter <daniel.vetter@ffwll.ch>
To: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: [PATCH] drm/i915: rip out pre-production ilk cpu edp w/a
Date: Thu, 13 Sep 2012 13:13:29 +0200 [thread overview]
Message-ID: <1347534809-13341-1-git-send-email-daniel.vetter@ffwll.ch> (raw)
While reading docs I've noticed that this special workaround to select
the 1.6 GHz DP clock only applies to pre-production ilk machines.
Since the registers we're touching here are rather undocumented and
might be harmful on later chips, rip it out.
For the Bspec reference of this w/a look in "vol4g CPU Display
Registers [DevILK]", Section 4.1.7.1 "DP_A—DisplayPort A
Control Register", "DP_PLL_Frequency_Select".
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
drivers/gpu/drm/i915/intel_dp.c | 22 +++-------------------
1 file changed, 3 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 376ae28..e2794ca 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -818,27 +818,11 @@ static void ironlake_set_pll_edp(struct drm_crtc *crtc, int clock)
dpa_ctl = I915_READ(DP_A);
dpa_ctl &= ~DP_PLL_FREQ_MASK;
- if (clock < 200000) {
- u32 temp;
+ if (clock < 200000)
dpa_ctl |= DP_PLL_FREQ_160MHZ;
- /* workaround for 160Mhz:
- 1) program 0x4600c bits 15:0 = 0x8124
- 2) program 0x46010 bit 0 = 1
- 3) program 0x46034 bit 24 = 1
- 4) program 0x64000 bit 14 = 1
- */
- temp = I915_READ(0x4600c);
- temp &= 0xffff0000;
- I915_WRITE(0x4600c, temp | 0x8124);
-
- temp = I915_READ(0x46010);
- I915_WRITE(0x46010, temp | 1);
-
- temp = I915_READ(0x46034);
- I915_WRITE(0x46034, temp | (1 << 24));
- } else {
+ else
dpa_ctl |= DP_PLL_FREQ_270MHZ;
- }
+
I915_WRITE(DP_A, dpa_ctl);
POSTING_READ(DP_A);
--
1.7.11.2
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
next reply other threads:[~2012-09-13 12:21 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-13 11:13 Daniel Vetter [this message]
2012-09-13 12:38 ` [PATCH] drm/i915: rip out pre-production ilk cpu edp w/a Chris Wilson
2012-09-13 14:11 ` Daniel Vetter
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1347534809-13341-1-git-send-email-daniel.vetter@ffwll.ch \
--to=daniel.vetter@ffwll.ch \
--cc=intel-gfx@lists.freedesktop.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox