habanalabs: add opcode to INFO IOCTL to return clock rate

Add a new opcode to the INFO IOCTL to allow the user application to
retrieve the ASIC's current and maximum clock rate. The rate is
returned in MHz.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Tomer Tayar <ttayar@habana.ai>

drivers/misc/habanalabs/goya/goya.c

@@ -5148,7 +5148,8 @@ static const struct hl_asic_funcs goya_funcs = {
 	.init_iatu = goya_init_iatu,
 	.rreg = hl_rreg,
 	.wreg = hl_wreg,
-	.halt_coresight = goya_halt_coresight
+	.halt_coresight = goya_halt_coresight,
+	.get_clk_rate = goya_get_clk_rate
 };
 
 /*

drivers/misc/habanalabs/goya/goyaP.h

@@ -233,4 +233,6 @@ void goya_cpu_accessible_dma_pool_free(struct hl_device *hdev, size_t size,
 					void *vaddr);
 void goya_mmu_remove_device_cpu_mappings(struct hl_device *hdev);
 
+int goya_get_clk_rate(struct hl_device *hdev, u32 *cur_clk, u32 *max_clk);
+
 #endif /* GOYAP_H_ */

drivers/misc/habanalabs/goya/goya_hwmgr.c

@@ -32,6 +32,37 @@ void goya_set_pll_profile(struct hl_device *hdev, enum hl_pll_frequency freq)
 	}
 }
 
+int goya_get_clk_rate(struct hl_device *hdev, u32 *cur_clk, u32 *max_clk)
+{
+	long value;
+
+	if (hl_device_disabled_or_in_reset(hdev))
+		return -ENODEV;
+
+	value = hl_get_frequency(hdev, MME_PLL, false);
+
+	if (value < 0) {
+		dev_err(hdev->dev, "Failed to retrieve device max clock %ld\n",
+			value);
+		return value;
+	}
+
+	*max_clk = (value / 1000 / 1000);
+
+	value = hl_get_frequency(hdev, MME_PLL, true);
+
+	if (value < 0) {
+		dev_err(hdev->dev,
+			"Failed to retrieve device current clock %ld\n",
+			value);
+		return value;
+	}
+
+	*cur_clk = (value / 1000 / 1000);
+
+	return 0;
+}
+
 static ssize_t mme_clk_show(struct device *dev, struct device_attribute *attr,
 				char *buf)
 {

drivers/misc/habanalabs/habanalabs.h

@@ -508,6 +508,7 @@ enum hl_pll_frequency {
  * @rreg: Read a register. Needed for simulator support.
  * @wreg: Write a register. Needed for simulator support.
  * @halt_coresight: stop the ETF and ETR traces.
+ * @get_clk_rate: Retrieve the ASIC current and maximum clock rate in MHz
  */
 struct hl_asic_funcs {
 	int (*early_init)(struct hl_device *hdev);
@@ -590,6 +591,7 @@ struct hl_asic_funcs {
 	u32 (*rreg)(struct hl_device *hdev, u32 reg);
 	void (*wreg)(struct hl_device *hdev, u32 reg, u32 val);
 	void (*halt_coresight)(struct hl_device *hdev);
+	int (*get_clk_rate)(struct hl_device *hdev, u32 *cur_clk, u32 *max_clk);
 };
 
 

drivers/misc/habanalabs/habanalabs_ioctl.c

@@ -221,6 +221,25 @@ static int device_utilization(struct hl_device *hdev, struct hl_info_args *args)
 		min((size_t) max_size, sizeof(device_util))) ? -EFAULT : 0;
 }
 
+static int get_clk_rate(struct hl_device *hdev, struct hl_info_args *args)
+{
+	struct hl_info_clk_rate clk_rate = {0};
+	u32 max_size = args->return_size;
+	void __user *out = (void __user *) (uintptr_t) args->return_pointer;
+	int rc;
+
+	if ((!max_size) || (!out))
+		return -EINVAL;
+
+	rc = hdev->asic_funcs->get_clk_rate(hdev, &clk_rate.cur_clk_rate_mhz,
+						&clk_rate.max_clk_rate_mhz);
+	if (rc)
+		return rc;
+
+	return copy_to_user(out, &clk_rate,
+		min((size_t) max_size, sizeof(clk_rate))) ? -EFAULT : 0;
+}
+
 static int _hl_info_ioctl(struct hl_fpriv *hpriv, void *data,
 				struct device *dev)
 {
@@ -271,6 +290,10 @@ static int _hl_info_ioctl(struct hl_fpriv *hpriv, void *data,
 		rc = hw_events_info(hdev, true, args);
 		break;
 
+	case HL_INFO_CLK_RATE:
+		rc = get_clk_rate(hdev, args);
+		break;
+
 	default:
 		dev_err(dev, "Invalid request %d\n", args->op);
 		rc = -ENOTTY;

include/uapi/misc/habanalabs.h

@@ -88,13 +88,16 @@ enum hl_device_status {
  *                         internal engine.
  * HL_INFO_DEVICE_STATUS - Retrieve the device's status. This opcode doesn't
  *                         require an open context.
- * HL_INFO_DEVICE_UTILIZATION - Retrieve the total utilization of the device
- *                              over the last period specified by the user.
- *                              The period can be between 100ms to 1s, in
- *                              resolution of 100ms. The return value is a
- *                              percentage of the utilization rate.
+ * HL_INFO_DEVICE_UTILIZATION  - Retrieve the total utilization of the device
+ *                               over the last period specified by the user.
+ *                               The period can be between 100ms to 1s, in
+ *                               resolution of 100ms. The return value is a
+ *                               percentage of the utilization rate.
  * HL_INFO_HW_EVENTS_AGGREGATE - Receive an array describing how many times each
  *                               event occurred since the driver was loaded.
+ * HL_INFO_CLK_RATE            - Retrieve the current and maximum clock rate
+ *                               of the device in MHz. The maximum clock rate is
+ *                               configurable via sysfs parameter
  */
 #define HL_INFO_HW_IP_INFO		0
 #define HL_INFO_HW_EVENTS		1
@@ -103,6 +106,7 @@ enum hl_device_status {
 #define HL_INFO_DEVICE_STATUS		4
 #define HL_INFO_DEVICE_UTILIZATION	6
 #define HL_INFO_HW_EVENTS_AGGREGATE	7
+#define HL_INFO_CLK_RATE		8
 
 #define HL_INFO_VERSION_MAX_LEN	128
 
@@ -149,6 +153,11 @@ struct hl_info_device_utilization {
 	__u32 pad;
 };
 
+struct hl_info_clk_rate {
+	__u32 cur_clk_rate_mhz;
+	__u32 max_clk_rate_mhz;
+};
+
 struct hl_info_args {
 	/* Location of relevant struct in userspace */
 	__u64 return_pointer;