Stefan Reinauer (stefan.reinauer@coreboot.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/1268
-gerrit
commit 696dc0b6d66d34d0c15798f365387ff8f1436e17 Author: Duncan Laurie dlaurie@chromium.org Date: Fri May 25 10:04:17 2012 -0700
Fixes to enable RC6 on IvyBridge
- The unneeded poll on non-MT force-wake bit was timing out and causing the gma_pm_init_pre_vbios() function to exit early so it was not preparing PM registers properly. I changed the gtt_poll() calls to not return on timeout unless it can't proceed so we don't see half-initialized registers.
- RC6+ (Deep Render Standby) is not working reliably so we can just enable RC6 in the BIOS and let the kernel decide if it wants to enable RC6+ later.
This Kernel message is new in kernel 3.4: [drm] Enabling RC6 states: RC6 on, RC6p off, RC6pp off
Change-Id: I69d005ba56be8c7684a4ea1133a1d761f7c07acc Signed-off-by: Duncan Laurie dlaurie@chromium.org --- src/northbridge/intel/sandybridge/gma.c | 59 +++++++++++-------------------- 1 files changed, 21 insertions(+), 38 deletions(-)
diff --git a/src/northbridge/intel/sandybridge/gma.c b/src/northbridge/intel/sandybridge/gma.c index 499f347..9a8b631 100644 --- a/src/northbridge/intel/sandybridge/gma.c +++ b/src/northbridge/intel/sandybridge/gma.c @@ -374,19 +374,11 @@ static void gma_pm_init_pre_vbios(struct device *dev) if (bridge_silicon_revision() < IVB_STEP_C0) { /* 1: Enable force wake */ gtt_write(0xa18c, 0x00000001); - if (!gtt_poll(0x130090, (1 << 0), (1 << 0))) - return; + gtt_poll(0x130090, (1 << 0), (1 << 0)); } else { gtt_write(0xa180, 1 << 5); gtt_write(0xa188, 0xffff0001); - if (!gtt_poll(0x130040, (1 << 0), (1 << 0))) - return; - /* - * HACK: also poll on 0x130090, for some reason graphics does - * not work on all SKUs unless this register is polled at boot. - */ - if (!gtt_poll(0x130090, (1 << 0), (1 << 0))) - return; + gtt_poll(0x130040, (1 << 0), (1 << 0)); }
if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_SNB) { @@ -432,7 +424,7 @@ static void gma_pm_init_pre_vbios(struct device *dev) gtt_write_powermeter(ivb_pm_gt2_17w); } else if ((tdp >= 25) && (tdp <= 35)) { /* 25W-35W */ - printk(BIOS_DEBUG, "IVB GT2 35W " + printk(BIOS_DEBUG, "IVB GT2 25W-35W " "Power Meter Weights\n"); gtt_write_powermeter(ivb_pm_gt2_35w); } else { @@ -472,8 +464,7 @@ static void gma_pm_init_pre_vbios(struct device *dev) reg32 &= 0xf; reg32 |= (1 << 1); gtt_write(0x941c, reg32); - if (!gtt_poll(0x941c, (1 << 1), (0 << 1))) - return; + gtt_poll(0x941c, (1 << 1), (0 << 1)); }
if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_IVB) { @@ -489,15 +480,13 @@ static void gma_pm_init_pre_vbios(struct device *dev) }
/* 7 */ - if (!gtt_poll(0x138124, (1 << 31), (0 << 31))) - return; - gtt_write(0x138128, 0x00000029); /* Mailbox Data */ - gtt_write(0x138124, 0x80000004); /* Mailbox Cmd for RC6 VID */ - if (!gtt_poll(0x138124, (1 << 31), (0 << 31))) - return; - gtt_write(0x138124, 0x8000000a); /* Mailbox Cmd to clear RC6 count */ - if (!gtt_poll(0x138124, (1 << 31), (0 << 31))) - return; + if (gtt_poll(0x138124, (1 << 31), (0 << 31))) { + gtt_write(0x138128, 0x00000029); /* Mailbox Data */ + gtt_write(0x138124, 0x80000004); /* Mailbox Cmd for RC6 VID */ + if (gtt_poll(0x138124, (1 << 31), (0 << 31))) + gtt_write(0x138124, 0x8000000a); + gtt_poll(0x138124, (1 << 31), (0 << 31)); + }
/* 8 */ gtt_write(0xa090, 0x00000000); /* RC Control */ @@ -530,8 +519,13 @@ static void gma_pm_init_pre_vbios(struct device *dev)
/* 11a: Enable Render Standby (RC6) */ if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_IVB) { - /* on IVB: also enable DeepRenderStandby */ - gtt_write(0xa090, 0x88060000); /* HW RC Control */ + /* + * IvyBridge should also support DeepRenderStandby. + * + * Unfortunately it does not work reliably on all SKUs so + * disable it here and it can be enabled by the kernel. + */ + gtt_write(0xa090, 0x88040000); /* HW RC Control */ } else { gtt_write(0xa090, 0x88040000); /* HW RC Control */ } @@ -566,22 +560,11 @@ static void gma_pm_init_post_vbios(struct device *dev) /* 15: Deassert Force Wake */ if (bridge_silicon_revision() < IVB_STEP_C0) { gtt_write(0xa18c, gtt_read(0xa18c) & ~1); - if (!gtt_poll(0x130090, (1 << 0), (0 << 0))) { - return; - } + gtt_poll(0x130090, (1 << 0), (0 << 0)); } else { gtt_write(0xa188, 0x1fffe); - if (!gtt_poll(0x130040, (1 << 0), (0 << 0))) { - return; - } - /* - * HACK: also poll on 0x130090, for some reason graphics does - * not work on all SKUs unless this register is polled at boot. - */ - if (!gtt_poll(0x130090, (1 << 0), (0 << 0))) { - return; - } - gtt_write(0xa188, gtt_read(0xa188) | 1); + if (gtt_poll(0x130040, (1 << 0), (0 << 0))) + gtt_write(0xa188, gtt_read(0xa188) | 1); }
/* 16: SW RC Control */