drm/amd/amdgpu: Enabling ACP clock in hw_init (v2)

Enabling of ACP in hw_init does away with requirement of order
of probe on designware_i2s and acp dma driver. designware_i2s
reads i2s registers and this use to fail if acp dma driver was not probed
prior to it.

BUG=:b:62103837
TEST=modprobe snd-soc-acp-pcm
modprobe snd-soc-acp-rt5645-mach
aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: acprt5650 [acprt5650], device 0: RT5645_AIF1 rt5645-aif1-0 []
  Subdevices: 1/1
    Subdevice #0: subdevice #0

v2: use proper device in dev_err to fix warnings (Alex)
Signed-off-by: Akshu Agrawal <akshu.agrawal@amd.com>
Reviewed-on: https://chromium-review.googlesource.com/670207Reviewed-by: Jason Clinton <jclinton@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/676628Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_acp.c

@@ -67,6 +67,15 @@
 #define mmACP_MEM_SHUT_DOWN_STS_LO		0x51fa
 #define mmACP_MEM_SHUT_DOWN_STS_HI		0x51fb
 
+#define mmACP_CONTROL				0x5131
+#define mmACP_STATUS				0x5133
+#define mmACP_SOFT_RESET			0x5134
+#define ACP_CONTROL__ClkEn_MASK 		0x1
+#define ACP_SOFT_RESET__SoftResetAud_MASK 	0x100
+#define ACP_SOFT_RESET__SoftResetAudDone_MASK	0x1000000
+#define ACP_CLOCK_EN_TIME_OUT_VALUE		0x000000FF
+#define ACP_SOFT_RESET_DONE_TIME_OUT_VALUE	0x000000FF
+
 #define ACP_TIMEOUT_LOOP			0x000000FF
 #define ACP_DEVS				3
 #define ACP_SRC_ID				162
@@ -260,6 +269,8 @@ static int acp_hw_init(void *handle)
 {
 	int r, i;
 	uint64_t acp_base;
+	u32 val = 0;
+	u32 count = 0;
 	struct device *dev;
 	struct i2s_platform_data *i2s_pdata;
 
@@ -400,6 +411,46 @@ static int acp_hw_init(void *handle)
 		}
 	}
 
+	/* Assert Soft reset of ACP */
+	val = cgs_read_register(adev->acp.cgs_device, mmACP_SOFT_RESET);
+
+	val |= ACP_SOFT_RESET__SoftResetAud_MASK;
+	cgs_write_register(adev->acp.cgs_device, mmACP_SOFT_RESET, val);
+
+	count = ACP_SOFT_RESET_DONE_TIME_OUT_VALUE;
+	while (true) {
+		val = cgs_read_register(adev->acp.cgs_device, mmACP_SOFT_RESET);
+		if (ACP_SOFT_RESET__SoftResetAudDone_MASK ==
+		    (val & ACP_SOFT_RESET__SoftResetAudDone_MASK))
+			break;
+		if (--count == 0) {
+			dev_err(&adev->pdev->dev, "Failed to reset ACP\n");
+			return -ETIMEDOUT;
+		}
+		udelay(100);
+	}
+	/* Enable clock to ACP and wait until the clock is enabled */
+	val = cgs_read_register(adev->acp.cgs_device, mmACP_CONTROL);
+	val = val | ACP_CONTROL__ClkEn_MASK;
+	cgs_write_register(adev->acp.cgs_device, mmACP_CONTROL, val);
+
+	count = ACP_CLOCK_EN_TIME_OUT_VALUE;
+
+	while (true) {
+		val = cgs_read_register(adev->acp.cgs_device, mmACP_STATUS);
+		if (val & (u32) 0x1)
+			break;
+		if (--count == 0) {
+			dev_err(&adev->pdev->dev, "Failed to reset ACP\n");
+			return -ETIMEDOUT;
+		}
+		udelay(100);
+	}
+	/* Deassert the SOFT RESET flags */
+	val = cgs_read_register(adev->acp.cgs_device, mmACP_SOFT_RESET);
+	val &= ~ACP_SOFT_RESET__SoftResetAud_MASK;
+	cgs_write_register(adev->acp.cgs_device, mmACP_SOFT_RESET, val);
+
 	return 0;
 }
 
@@ -412,6 +463,8 @@ static int acp_hw_init(void *handle)
 static int acp_hw_fini(void *handle)
 {
 	int i, ret;
+	u32 val = 0;
+	u32 count = 0;
 	struct device *dev;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 
@@ -419,6 +472,42 @@ static int acp_hw_fini(void *handle)
 	if (!adev->acp.acp_cell)
 		return 0;
 
+	/* Assert Soft reset of ACP */
+	val = cgs_read_register(adev->acp.cgs_device, mmACP_SOFT_RESET);
+
+	val |= ACP_SOFT_RESET__SoftResetAud_MASK;
+	cgs_write_register(adev->acp.cgs_device, mmACP_SOFT_RESET, val);
+
+	count = ACP_SOFT_RESET_DONE_TIME_OUT_VALUE;
+	while (true) {
+		val = cgs_read_register(adev->acp.cgs_device, mmACP_SOFT_RESET);
+		if (ACP_SOFT_RESET__SoftResetAudDone_MASK ==
+		    (val & ACP_SOFT_RESET__SoftResetAudDone_MASK))
+			break;
+		if (--count == 0) {
+			dev_err(&adev->pdev->dev, "Failed to reset ACP\n");
+			return -ETIMEDOUT;
+		}
+		udelay(100);
+	}
+	/* Disable ACP clock */
+	val = cgs_read_register(adev->acp.cgs_device, mmACP_CONTROL);
+	val &= ~ACP_CONTROL__ClkEn_MASK;
+	cgs_write_register(adev->acp.cgs_device, mmACP_CONTROL, val);
+
+	count = ACP_CLOCK_EN_TIME_OUT_VALUE;
+
+	while (true) {
+		val = cgs_read_register(adev->acp.cgs_device, mmACP_STATUS);
+		if (val & (u32) 0x1)
+			break;
+		if (--count == 0) {
+			dev_err(&adev->pdev->dev, "Failed to reset ACP\n");
+			return -ETIMEDOUT;
+		}
+		udelay(100);
+	}
+
 	if (adev->acp.acp_genpd) {
 		for (i = 0; i < ACP_DEVS ; i++) {
 			dev = get_mfd_cell_dev(adev->acp.acp_cell[i].name, i);