[PATCH] drm/i915: fixup sbi_read/write locking

[PATCH] drm/i915: fixup sbi_read/write locking

[daniel.vetter]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

commit 09153000b8ca32a539a1207edebabd0d40b6c61b
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Dec 12 14:06:44 2012 +0100

    drm/i915: rework locking for intel_dpio|sbi_read|write

reworked the locking around sbi_read/write functions for 3.8-fixes.
But

commit dde86e2db54545ef981b64805097a7b4c3156d6e
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Sat Dec 1 12:04:25 2012 -0200

    drm/i915: add lpt_init_pch_refcl

Added new use-cases in the -next tree which has not been updated in
the merge. Fix it up.

Reported-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/intel_display.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 26df9e3..27fe702 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4871,6 +4871,8 @@ static void lpt_init_pch_refclk(struct drm_device *dev)
 	if (!has_vga)
 		return;
 
+	mutex_lock(&dev_priv->dpio_lock);
+
 	/* XXX: Rip out SDV support once Haswell ships for real. */
 	if (IS_HASWELL(dev) && (dev->pci_device & 0xFF00) == 0x0C00)
 		is_sdv = true;
@@ -5013,6 +5015,8 @@ static void lpt_init_pch_refclk(struct drm_device *dev)
 	tmp = intel_sbi_read(dev_priv, SBI_DBUFF0, SBI_ICLK);
 	tmp |= SBI_DBUFF0_ENABLE;
 	intel_sbi_write(dev_priv, SBI_DBUFF0, tmp, SBI_ICLK);
+
+	mutex_unlock(&dev_priv->dpio_lock);
 }
 
 /*
-- 
1.7.10.4

Re: [PATCH] drm/i915: fixup sbi_read/write locking

[Ben Widawsky]

On Tue, 22 Jan 2013 15:33:27 +0100
daniel.vetter@ffwll.ch wrote:

> From: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> commit 09153000b8ca32a539a1207edebabd0d40b6c61b
> Author: Daniel Vetter <daniel.vetter@ffwll.ch>
> Date:   Wed Dec 12 14:06:44 2012 +0100
> 
>     drm/i915: rework locking for intel_dpio|sbi_read|write
> 
> reworked the locking around sbi_read/write functions for 3.8-fixes.
> But
> 
> commit dde86e2db54545ef981b64805097a7b4c3156d6e
> Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
> Date:   Sat Dec 1 12:04:25 2012 -0200
> 
>     drm/i915: add lpt_init_pch_refcl
> 
> Added new use-cases in the -next tree which has not been updated in
> the merge. Fix it up.
> 
> Reported-by: Ben Widawsky <ben@bwidawsk.net>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Ben Widawsky <ben@bwidawsk.net>

Re: [PATCH] drm/i915: fixup sbi_read/write locking

[Daniel Vetter]

On Tue, Jan 22, 2013 at 03:42:14PM -0800, Ben Widawsky wrote:
> On Tue, 22 Jan 2013 15:33:27 +0100
> daniel.vetter@ffwll.ch wrote:
> 
> > From: Daniel Vetter <daniel.vetter@ffwll.ch>
> > 
> > commit 09153000b8ca32a539a1207edebabd0d40b6c61b
> > Author: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Date:   Wed Dec 12 14:06:44 2012 +0100
> > 
> >     drm/i915: rework locking for intel_dpio|sbi_read|write
> > 
> > reworked the locking around sbi_read/write functions for 3.8-fixes.
> > But
> > 
> > commit dde86e2db54545ef981b64805097a7b4c3156d6e
> > Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
> > Date:   Sat Dec 1 12:04:25 2012 -0200
> > 
> >     drm/i915: add lpt_init_pch_refcl
> > 
> > Added new use-cases in the -next tree which has not been updated in
> > the merge. Fix it up.
> > 
> > Reported-by: Ben Widawsky <ben@bwidawsk.net>
> > Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
> Tested-by: Ben Widawsky <ben@bwidawsk.net>

Queued for -next, thanks for the review.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch