drm/msm: Add adreno_gpu_write64()

Add a new generic function to write a "64" bit value. This isn't
actually a 64 bit operation, it just writes the upper and lower
32 bit of a 64 bit value to a specified LO and HI register.  If
a particular target doesn't support one of the registers it can
mark that register as SKIP and writes/reads from that register
will be quietly dropped.

This can be immediately put in place for the ringbuffer base and
the RPTR address.  Both writes are converted to use
adreno_gpu_write64() with their respective high and low registers
and the high register appropriately marked as SKIP for both 32 bit
targets (a3xx and a4xx). When a5xx comes it will define valid target
registers for the 'hi' option and everything else will just work.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/adreno/a3xx_gpu.c

@@ -430,7 +430,9 @@ static void a3xx_dump(struct msm_gpu *gpu)
 /* Register offset defines for A3XX */
 static const unsigned int a3xx_register_offsets[REG_ADRENO_REGISTER_MAX] = {
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_BASE, REG_AXXX_CP_RB_BASE),
+	REG_ADRENO_SKIP(REG_ADRENO_CP_RB_BASE_HI),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_RPTR_ADDR, REG_AXXX_CP_RB_RPTR_ADDR),
+	REG_ADRENO_SKIP(REG_ADRENO_CP_RB_RPTR_ADDR_HI),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_RPTR, REG_AXXX_CP_RB_RPTR),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_WPTR, REG_AXXX_CP_RB_WPTR),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_CNTL, REG_AXXX_CP_RB_CNTL),

drivers/gpu/drm/msm/adreno/a4xx_gpu.c

@@ -470,7 +470,9 @@ static void a4xx_show(struct msm_gpu *gpu, struct seq_file *m)
 /* Register offset defines for A4XX, in order of enum adreno_regs */
 static const unsigned int a4xx_register_offsets[REG_ADRENO_REGISTER_MAX] = {
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_BASE, REG_A4XX_CP_RB_BASE),
+	REG_ADRENO_SKIP(REG_ADRENO_CP_RB_BASE_HI),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_RPTR_ADDR, REG_A4XX_CP_RB_RPTR_ADDR),
+	REG_ADRENO_SKIP(REG_ADRENO_CP_RB_RPTR_ADDR_HI),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_RPTR, REG_A4XX_CP_RB_RPTR),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_WPTR, REG_A4XX_CP_RB_WPTR),
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_CNTL, REG_A4XX_CP_RB_CNTL),

drivers/gpu/drm/msm/adreno/adreno_gpu.c

@@ -79,11 +79,14 @@ int adreno_hw_init(struct msm_gpu *gpu)
 			(adreno_is_a430(adreno_gpu) ? AXXX_CP_RB_CNTL_NO_UPDATE : 0));
 
 	/* Setup ringbuffer address: */
-	adreno_gpu_write(adreno_gpu, REG_ADRENO_CP_RB_BASE, gpu->rb_iova);
+	adreno_gpu_write64(adreno_gpu, REG_ADRENO_CP_RB_BASE,
+		REG_ADRENO_CP_RB_BASE_HI, gpu->rb_iova);
 
-	if (!adreno_is_a430(adreno_gpu))
-		adreno_gpu_write(adreno_gpu, REG_ADRENO_CP_RB_RPTR_ADDR,
-						rbmemptr(adreno_gpu, rptr));
+	if (!adreno_is_a430(adreno_gpu)) {
+		adreno_gpu_write64(adreno_gpu, REG_ADRENO_CP_RB_RPTR_ADDR,
+			REG_ADRENO_CP_RB_RPTR_ADDR_HI,
+			rbmemptr(adreno_gpu, rptr));
+	}
 
 	return 0;
 }

drivers/gpu/drm/msm/adreno/adreno_gpu.h

@@ -28,6 +28,9 @@
 #include "adreno_pm4.xml.h"
 
 #define REG_ADRENO_DEFINE(_offset, _reg) [_offset] = (_reg) + 1
+#define REG_SKIP ~0
+#define REG_ADRENO_SKIP(_offset) [_offset] = REG_SKIP
+
 /**
  * adreno_regs: List of registers that are used in across all
  * 3D devices. Each device type has different offset value for the same
@@ -36,7 +39,9 @@
  */
 enum adreno_regs {
 	REG_ADRENO_CP_RB_BASE,
+	REG_ADRENO_CP_RB_BASE_HI,
 	REG_ADRENO_CP_RB_RPTR_ADDR,
+	REG_ADRENO_CP_RB_RPTR_ADDR_HI,
 	REG_ADRENO_CP_RB_RPTR,
 	REG_ADRENO_CP_RB_WPTR,
 	REG_ADRENO_CP_RB_CNTL,
@@ -220,7 +225,7 @@ OUT_PKT3(struct msm_ringbuffer *ring, uint8_t opcode, uint16_t cnt)
 }
 
 /*
- * adreno_checkreg_off() - Checks the validity of a register enum
+ * adreno_reg_check() - Checks the validity of a register enum
  * @gpu:		Pointer to struct adreno_gpu
  * @offset_name:	The register enum that is checked
  */
@@ -231,6 +236,16 @@ static inline bool adreno_reg_check(struct adreno_gpu *gpu,
 			!gpu->reg_offsets[offset_name]) {
 		BUG();
 	}
+
+	/*
+	 * REG_SKIP is a special value that tell us that the register in
+	 * question isn't implemented on target but don't trigger a BUG(). This
+	 * is used to cleanly implement adreno_gpu_write64() and
+	 * adreno_gpu_read64() in a generic fashion
+	 */
+	if (gpu->reg_offsets[offset_name] == REG_SKIP)
+		return false;
+
 	return true;
 }
 
@@ -255,4 +270,11 @@ static inline void adreno_gpu_write(struct adreno_gpu *gpu,
 struct msm_gpu *a3xx_gpu_init(struct drm_device *dev);
 struct msm_gpu *a4xx_gpu_init(struct drm_device *dev);
 
+static inline void adreno_gpu_write64(struct adreno_gpu *gpu,
+		enum adreno_regs lo, enum adreno_regs hi, u64 data)
+{
+	adreno_gpu_write(gpu, lo, lower_32_bits(data));
+	adreno_gpu_write(gpu, hi, upper_32_bits(data));
+}
+
 #endif /* __ADRENO_GPU_H__ */