[PATCH V7 RESEND 1/7] soc: qcom: geni: Support for ICC voting

[Akash Asthana <akashast@xxxxxxxxxxxxxx>]

Add necessary macros and structure variables to support ICC BW
voting from individual SE drivers.

Signed-off-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
---
Changes in V2:
 - As per Bjorn's comment dropped enums for ICC paths, given the three
   paths individual members

Changes in V3:
 - Add geni_icc_get, geni_icc_vote_on and geni_icc_vote_off as helper API.
 - Add geni_icc_path structure in common header

Changes in V4:
 - As per Bjorn's comment print error message in geni_icc_get if return
   value is not -EPROBE_DEFER.
 - As per Bjorn's comment remove NULL on path before calling icc_set_bw
   API.
 - As per Bjorn's comment drop __func__ print.
 - As per Matthias's comment, make ICC path a array instead of individual
   member entry in geni_se struct.

Changes in V5:
 - As per Matthias's comment defined enums for ICC paths.
 - Integrate icc_enable/disable with power on/off call for driver.
 - As per Matthias's comment added icc_path_names array to print icc path name
   in failure case.
 - As per Georgi's suggestion assume peak_bw = avg_bw if not mentioned.

Changes in V6:
 - Addressed nitpicks from Matthias.

Changes in V7:
 - As per Matthias's comment removed usage of peak_bw variable because we don't
   have explicit peak requirement, we were voting peak = avg and this can be
   tracked using single variable for avg bw.
 - As per Matthias's comment improved print log.

Note: I have ignored below check patch suggestion because it was throwing
      compilation error as 'icc_ddr' is not compile time comstant.

WARNING: char * array declaration might be better as static const
 - FILE: drivers/soc/qcom/qcom-geni-se.c:726:
 - const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};

 drivers/soc/qcom/qcom-geni-se.c | 82 +++++++++++++++++++++++++++++++++++++++++
 include/linux/qcom-geni-se.h    | 38 +++++++++++++++++++
 2 files changed, 120 insertions(+)

diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
index 7d622ea..950e347 100644
--- a/drivers/soc/qcom/qcom-geni-se.c
+++ b/drivers/soc/qcom/qcom-geni-se.c
@@ -92,6 +92,9 @@ struct geni_wrapper {
 	struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
 };
 
+static const char * const icc_path_names[] = {"qup-core", "qup-config",
+						"qup-memory"};
+
 #define QUP_HW_VER_REG			0x4
 
 /* Common SE registers */
@@ -720,6 +723,85 @@ void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
 }
 EXPORT_SYMBOL(geni_se_rx_dma_unprep);
 
+int geni_icc_get(struct geni_se *se, const char *icc_ddr)
+{
+	int i, err;
+	const char *icc_names[] = {"qup-core", "qup-config", icc_ddr};
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
+		if (!icc_names[i])
+			continue;
+
+		se->icc_paths[i].path = devm_of_icc_get(se->dev, icc_names[i]);
+		if (IS_ERR(se->icc_paths[i].path))
+			goto err;
+	}
+
+	return 0;
+
+err:
+	err = PTR_ERR(se->icc_paths[i].path);
+	if (err != -EPROBE_DEFER)
+		dev_err_ratelimited(se->dev, "Failed to get ICC path '%s': %d\n",
+					icc_names[i], err);
+	return err;
+
+}
+EXPORT_SYMBOL(geni_icc_get);
+
+int geni_icc_set_bw(struct geni_se *se)
+{
+	int i, ret;
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
+		ret = icc_set_bw(se->icc_paths[i].path,
+			se->icc_paths[i].avg_bw, se->icc_paths[i].avg_bw);
+		if (ret) {
+			dev_err_ratelimited(se->dev, "ICC BW voting failed on path '%s': %d\n",
+					icc_path_names[i], ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(geni_icc_set_bw);
+
+/* To do: Replace this by icc_bulk_enable once it's implemented in ICC core */
+int geni_icc_enable(struct geni_se *se)
+{
+	int i, ret;
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
+		ret = icc_enable(se->icc_paths[i].path);
+		if (ret) {
+			dev_err_ratelimited(se->dev, "ICC enable failed on path '%s': %d\n",
+					icc_path_names[i], ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(geni_icc_enable);
+
+int geni_icc_disable(struct geni_se *se)
+{
+	int i, ret;
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_paths); i++) {
+		ret = icc_disable(se->icc_paths[i].path);
+		if (ret) {
+			dev_err_ratelimited(se->dev, "ICC disable failed on path '%s': %d\n",
+					icc_path_names[i], ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(geni_icc_disable);
+
 static int geni_se_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h
index dd46494..80dbc01 100644
--- a/include/linux/qcom-geni-se.h
+++ b/include/linux/qcom-geni-se.h
@@ -6,6 +6,8 @@
 #ifndef _LINUX_QCOM_GENI_SE
 #define _LINUX_QCOM_GENI_SE
 
+#include <linux/interconnect.h>
+
 /* Transfer mode supported by GENI Serial Engines */
 enum geni_se_xfer_mode {
 	GENI_SE_INVALID,
@@ -25,6 +27,17 @@ enum geni_se_protocol_type {
 struct geni_wrapper;
 struct clk;
 
+enum geni_icc_path_index {
+	GENI_TO_CORE,
+	CPU_TO_GENI,
+	GENI_TO_DDR
+};
+
+struct geni_icc_path {
+	struct icc_path *path;
+	unsigned int avg_bw;
+};
+
 /**
  * struct geni_se - GENI Serial Engine
  * @base:		Base Address of the Serial Engine's register block
@@ -33,6 +46,7 @@ struct clk;
  * @clk:		Handle to the core serial engine clock
  * @num_clk_levels:	Number of valid clock levels in clk_perf_tbl
  * @clk_perf_tbl:	Table of clock frequency input to serial engine clock
+ * @icc_paths:		Array of ICC paths for SE
  */
 struct geni_se {
 	void __iomem *base;
@@ -41,6 +55,7 @@ struct geni_se {
 	struct clk *clk;
 	unsigned int num_clk_levels;
 	unsigned long *clk_perf_tbl;
+	struct geni_icc_path icc_paths[3];
 };
 
 /* Common SE registers */
@@ -229,6 +244,21 @@ struct geni_se {
 #define GENI_SE_VERSION_MINOR(ver) ((ver & HW_VER_MINOR_MASK) >> HW_VER_MINOR_SHFT)
 #define GENI_SE_VERSION_STEP(ver) (ver & HW_VER_STEP_MASK)
 
+/*
+ * Define bandwidth thresholds that cause the underlying Core 2X interconnect
+ * clock to run at the named frequency. These baseline values are recommended
+ * by the hardware team, and are not dynamically scaled with GENI bandwidth
+ * beyond basic on/off.
+ */
+#define CORE_2X_19_2_MHZ		960
+#define CORE_2X_50_MHZ			2500
+#define CORE_2X_100_MHZ			5000
+#define CORE_2X_150_MHZ			7500
+#define CORE_2X_200_MHZ			10000
+#define CORE_2X_236_MHZ			16383
+
+#define GENI_DEFAULT_BW			Bps_to_icc(1000)
+
 #if IS_ENABLED(CONFIG_QCOM_GENI_SE)
 
 u32 geni_se_get_qup_hw_version(struct geni_se *se);
@@ -416,5 +446,13 @@ int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
 void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len);
 
 void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len);
+
+int geni_icc_get(struct geni_se *se, const char *icc_ddr);
+
+int geni_icc_set_bw(struct geni_se *se);
+
+int geni_icc_enable(struct geni_se *se);
+
+int geni_icc_disable(struct geni_se *se);
 #endif
 #endif
-- 
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