platform/mellanox: mlxbf-pmc: Add support for clock_measure performance block

The HW clock_measure counter info is passed to the driver from ACPI.
Create a new sub-directory for clock_measure events and provide
read access to the user. Writes are blocked since the fields are RO.

Signed-off-by: Shravan Kumar Ramani <[e-mail]>
Reviewed-by: David Thompson <[e-mail]>
Reviewed-by: Vadim Pasternak <[e-mail]>
Link: https://lore.kernel.org/r/6[e-mail]
Reviewed-by: Ilpo Järvinen <[e-mail]>
Signed-off-by: Ilpo Järvinen <[e-mail]>

drivers/platform/mellanox/mlxbf-pmc.c

···
 	{75, "HISTOGRAM_HISTOGRAM_BIN9"},
 };
 
+static const struct mlxbf_pmc_events mlxbf_pmc_clock_events[] = {
+	{ 0x0, "FMON_CLK_LAST_COUNT_PLL_D1_INST0" },
+	{ 0x4, "REFERENCE_WINDOW_WIDTH_PLL_D1_INST0" },
+	{ 0x8, "FMON_CLK_LAST_COUNT_PLL_D1_INST1" },
+	{ 0xc, "REFERENCE_WINDOW_WIDTH_PLL_D1_INST1" },
+	{ 0x10, "FMON_CLK_LAST_COUNT_PLL_G1" },
+	{ 0x14, "REFERENCE_WINDOW_WIDTH_PLL_G1" },
+	{ 0x18, "FMON_CLK_LAST_COUNT_PLL_W1" },
+	{ 0x1c, "REFERENCE_WINDOW_WIDTH_PLL_W1" },
+	{ 0x20, "FMON_CLK_LAST_COUNT_PLL_T1" },
+	{ 0x24, "REFERENCE_WINDOW_WIDTH_PLL_T1" },
+	{ 0x28, "FMON_CLK_LAST_COUNT_PLL_A0" },
+	{ 0x2c, "REFERENCE_WINDOW_WIDTH_PLL_A0" },
+	{ 0x30, "FMON_CLK_LAST_COUNT_PLL_C0" },
+	{ 0x34, "REFERENCE_WINDOW_WIDTH_PLL_C0" },
+	{ 0x38, "FMON_CLK_LAST_COUNT_PLL_N1" },
+	{ 0x3c, "REFERENCE_WINDOW_WIDTH_PLL_N1" },
+	{ 0x40, "FMON_CLK_LAST_COUNT_PLL_I1" },
+	{ 0x44, "REFERENCE_WINDOW_WIDTH_PLL_I1" },
+	{ 0x48, "FMON_CLK_LAST_COUNT_PLL_R1" },
+	{ 0x4c, "REFERENCE_WINDOW_WIDTH_PLL_R1" },
+	{ 0x50, "FMON_CLK_LAST_COUNT_PLL_P1" },
+	{ 0x54, "REFERENCE_WINDOW_WIDTH_PLL_P1" },
+	{ 0x58, "FMON_CLK_LAST_COUNT_REF_100_INST0" },
+	{ 0x5c, "REFERENCE_WINDOW_WIDTH_REF_100_INST0" },
+	{ 0x60, "FMON_CLK_LAST_COUNT_REF_100_INST1" },
+	{ 0x64, "REFERENCE_WINDOW_WIDTH_REF_100_INST1" },
+	{ 0x68, "FMON_CLK_LAST_COUNT_REF_156" },
+	{ 0x6c, "REFERENCE_WINDOW_WIDTH_REF_156" },
+};
+
 static struct mlxbf_pmc_context *pmc;
 
 /* UUID used to probe ATF service. */
···
 	} else if (strstr(blk, "llt")) {
 		events = mlxbf_pmc_llt_events;
 		size = ARRAY_SIZE(mlxbf_pmc_llt_events);
+	} else if (strstr(blk, "clock_measure")) {
+		events = mlxbf_pmc_clock_events;
+		size = ARRAY_SIZE(mlxbf_pmc_clock_events);
 	} else {
 		events = NULL;
 		size = 0;
···
 /* Method to read a register */
 static int mlxbf_pmc_read_reg(unsigned int blk_num, u32 offset, u64 *result)
 {
-	u32 ecc_out;
+	u32 reg;
 
-	if (strstr(pmc->block_name[blk_num], "ecc")) {
+	if ((strstr(pmc->block_name[blk_num], "ecc")) ||
+	    (strstr(pmc->block_name[blk_num], "clock_measure"))) {
 		if (mlxbf_pmc_readl(pmc->block[blk_num].mmio_base + offset,
-				    &ecc_out))
+				    &reg))
 			return -EFAULT;
 
-		*result = ecc_out;
+		*result = reg;
 		return 0;
 	}
 
···
 /* Method to write to a register */
 static int mlxbf_pmc_write_reg(unsigned int blk_num, u32 offset, u64 data)
 {
+	if (strstr(pmc->block_name[blk_num], "clock_measure"))
+		return -EINVAL;
+
 	if (strstr(pmc->block_name[blk_num], "ecc")) {
 		return mlxbf_pmc_write(pmc->block[blk_num].mmio_base + offset,
 				       MLXBF_PMC_WRITE_REG_32, data);