[Intel-gfx] [PATCH 1/2] drm/i915/reg: fix undefined behavior due to shift overflowing the constant

Jani Nikula jani.nikula at intel.com
Wed May 18 11:33:14 UTC 2022


Use REG_GENMASK() and REG_FIELD_PREP() to avoid errors due to
-fsanitize=shift.

References: https://lore.kernel.org/r/20220405151517.29753-12-bp@alien8.de
Reported-by: Borislav Petkov <bp at suse.de>
Reported-by: Ruiqi GONG <gongruiqi1 at huawei.com>
Cc: Randy Dunlap <rdunlap at infradead.org>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 321a08281a3f..dff3f88d8090 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7607,25 +7607,25 @@ enum skl_power_gate {
 #define _PORT_CLK_SEL_A			0x46100
 #define _PORT_CLK_SEL_B			0x46104
 #define PORT_CLK_SEL(port) _MMIO_PORT(port, _PORT_CLK_SEL_A, _PORT_CLK_SEL_B)
-#define  PORT_CLK_SEL_LCPLL_2700	(0 << 29)
-#define  PORT_CLK_SEL_LCPLL_1350	(1 << 29)
-#define  PORT_CLK_SEL_LCPLL_810		(2 << 29)
-#define  PORT_CLK_SEL_SPLL		(3 << 29)
-#define  PORT_CLK_SEL_WRPLL(pll)	(((pll) + 4) << 29)
-#define  PORT_CLK_SEL_WRPLL1		(4 << 29)
-#define  PORT_CLK_SEL_WRPLL2		(5 << 29)
-#define  PORT_CLK_SEL_NONE		(7 << 29)
-#define  PORT_CLK_SEL_MASK		(7 << 29)
+#define  PORT_CLK_SEL_MASK		REG_GENMASK(31, 29)
+#define  PORT_CLK_SEL_LCPLL_2700	REG_FIELD_PREP(PORT_CLK_SEL_MASK, 0)
+#define  PORT_CLK_SEL_LCPLL_1350	REG_FIELD_PREP(PORT_CLK_SEL_MASK, 1)
+#define  PORT_CLK_SEL_LCPLL_810		REG_FIELD_PREP(PORT_CLK_SEL_MASK, 2)
+#define  PORT_CLK_SEL_SPLL		REG_FIELD_PREP(PORT_CLK_SEL_MASK, 3)
+#define  PORT_CLK_SEL_WRPLL(pll)	REG_FIELD_PREP(PORT_CLK_SEL_MASK, 4 + (pll))
+#define  PORT_CLK_SEL_WRPLL1		REG_FIELD_PREP(PORT_CLK_SEL_MASK, 4)
+#define  PORT_CLK_SEL_WRPLL2		REG_FIELD_PREP(PORT_CLK_SEL_MASK, 5)
+#define  PORT_CLK_SEL_NONE		REG_FIELD_PREP(PORT_CLK_SEL_MASK, 7)
 
 /* On ICL+ this is the same as PORT_CLK_SEL, but all bits change. */
 #define DDI_CLK_SEL(port)		PORT_CLK_SEL(port)
-#define  DDI_CLK_SEL_NONE		(0x0 << 28)
-#define  DDI_CLK_SEL_MG			(0x8 << 28)
-#define  DDI_CLK_SEL_TBT_162		(0xC << 28)
-#define  DDI_CLK_SEL_TBT_270		(0xD << 28)
-#define  DDI_CLK_SEL_TBT_540		(0xE << 28)
-#define  DDI_CLK_SEL_TBT_810		(0xF << 28)
-#define  DDI_CLK_SEL_MASK		(0xF << 28)
+#define  DDI_CLK_SEL_MASK		REG_GENMASK(31, 28)
+#define  DDI_CLK_SEL_NONE		REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0x0)
+#define  DDI_CLK_SEL_MG			REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0x8)
+#define  DDI_CLK_SEL_TBT_162		REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0xC)
+#define  DDI_CLK_SEL_TBT_270		REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0xD)
+#define  DDI_CLK_SEL_TBT_540		REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0xE)
+#define  DDI_CLK_SEL_TBT_810		REG_FIELD_PREP(DDI_CLK_SEL_MASK, 0xF)
 
 /* Transcoder clock selection */
 #define _TRANS_CLK_SEL_A		0x46140
-- 
2.30.2



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