From a42f704b71b252705f34fbe60ea6f4a76f891a78 Mon Sep 17 00:00:00 2001 From: Damien Lespiau Date: Mon, 25 Mar 2013 15:16:14 +0000 Subject: [PATCH] drm/i915: Warn if a pipe is enabled with a bogus port If TRANS_DDI_FUNC_CTL has been wrongly programmed with an incorrect port, we are currently trying to read PORT_CLK_SEL(port) with an uninitialized value. Handle that case by returning PORT_CLK_SEL_NONE and warning about it. v2: Move the warning inside intel_ddi_get_crtc_pll (Paulo Zanoni) Signed-off-by: Damien Lespiau Reviewed-by: Paulo Zanoni Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_ddi.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index d26147c90599..258e38e08b6e 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -1160,7 +1160,7 @@ static uint32_t intel_ddi_get_crtc_pll(struct drm_i915_private *dev_priv, enum pipe pipe) { uint32_t temp, ret; - enum port port; + enum port port = I915_MAX_PORTS; enum transcoder cpu_transcoder = intel_pipe_to_cpu_transcoder(dev_priv, pipe); int i; @@ -1176,10 +1176,16 @@ static uint32_t intel_ddi_get_crtc_pll(struct drm_i915_private *dev_priv, port = i; } - ret = I915_READ(PORT_CLK_SEL(port)); - - DRM_DEBUG_KMS("Pipe %c connected to port %c using clock 0x%08x\n", - pipe_name(pipe), port_name(port), ret); + if (port == I915_MAX_PORTS) { + WARN(1, "Pipe %c enabled on an unknown port\n", + pipe_name(pipe)); + ret = PORT_CLK_SEL_NONE; + } else { + ret = I915_READ(PORT_CLK_SEL(port)); + DRM_DEBUG_KMS("Pipe %c connected to port %c using clock " + "0x%08x\n", pipe_name(pipe), port_name(port), + ret); + } return ret; } -- 2.30.2