lib: Add SG2044 CPPC support

Signed-off-by: haijiao.liu <haijiao.liu@sophgo.com>

lib/utils/cppc/Kconfig

@@ -14,6 +14,11 @@ config FDT_CPPC_RPMI
 	depends on FDT_MAILBOX && RPMI_MAILBOX
 	default n
 
+config FDT_CPPC_SG2044
+	bool "FDT SG2044 CPPC driver"
+	select FDT_CLK_SG2044
+	default n
+
 endif
 
 endmenu

lib/utils/cppc/fdt_cppc_sg2044.c

@@ -0,0 +1,115 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 Sophgo Inc.
+ *
+ * Authors:
+ *   Haijiao Liu <haijiao.liu@sophgo.com>
+ */
+
+#include <libfdt.h>
+#include <sbi/sbi_error.h>
+#include <sbi/sbi_string.h>
+#include <sbi/sbi_console.h>
+#include <sbi/sbi_ecall_interface.h>
+#include <sbi/sbi_clk.h>
+#include <sbi/sbi_cppc.h>
+#include <sbi_utils/cppc/fdt_cppc.h>
+
+#define CPPC_REGISTER_WIDTH	64
+#define CPPC_REGISTER_NOT_IMPLEMENTED	0
+
+static char clock_names[64];
+static uint64_t clk_granularity;
+
+static int sg2044_cppc_read(unsigned long reg, u64 *val)
+{
+	int rc = SBI_SUCCESS;
+
+	switch (reg) {
+	case SBI_CPPC_DESIRED_PERF:
+		*val = sbi_clk_get_rate(clock_names) / clk_granularity;
+		break;
+	default:
+		rc = SBI_ERR_NOT_SUPPORTED;
+	}
+
+	return rc;
+}
+
+static int sg2044_cppc_write(unsigned long reg, u64 val)
+{
+	int rc = SBI_SUCCESS;
+
+	switch (reg) {
+	case SBI_CPPC_DESIRED_PERF:
+		rc = sbi_clk_set_rate(clock_names, val * clk_granularity);
+		break;
+	default:
+		rc = SBI_ERR_NOT_SUPPORTED;
+	}
+
+	return rc;
+}
+
+static int sg2044_cppc_probe(unsigned long reg)
+{
+	int rc;
+
+	switch (reg) {
+	case SBI_CPPC_DESIRED_PERF:
+		rc = CPPC_REGISTER_WIDTH;
+		break;
+	default:
+		rc = CPPC_REGISTER_NOT_IMPLEMENTED;
+	}
+
+	return rc;
+}
+
+static struct sbi_cppc_device sbi_sg2044_cppc = {
+	.name		= "sg2044-cppc",
+	.cppc_read	= sg2044_cppc_read,
+	.cppc_write	= sg2044_cppc_write,
+	.cppc_probe	= sg2044_cppc_probe,
+};
+
+static int sg2044_cppc_cold_init(const void *fdt, int nodeoff,
+				 const struct fdt_match *match)
+{
+	const struct sbi_clk_device *clk;
+	const fdt32_t *val;
+	const char *name;
+	int len;
+
+	clk = sbi_clk_get_device(fdt);
+	if (!clk)
+		return SBI_ENODEV;
+
+	val = fdt_getprop(fdt, nodeoff, "step", &len);
+	if (!val)
+		return SBI_EINVAL;
+
+	clk_granularity = fdt32_to_cpu(val[0]);
+	clk_granularity = (clk_granularity << 32) | fdt32_to_cpu(val[1]);
+
+	name = fdt_getprop(fdt, nodeoff, "clock-names", &len);
+	if (!name)
+		return SBI_EINVAL;
+
+	sbi_strncpy(clock_names, name, MIN(sizeof(clock_names), len));
+
+	sbi_cppc_set_device(&sbi_sg2044_cppc);
+
+	return 0;
+}
+
+static const struct fdt_match sg2044_cppc_match[] = {
+	{ .compatible = "sophgo,sg2044-cppc" },
+	{},
+};
+
+struct fdt_driver fdt_cppc_sg2044 = {
+	.match_table = sg2044_cppc_match,
+	.init = sg2044_cppc_cold_init,
+};

lib/utils/cppc/objects.mk

@@ -12,3 +12,6 @@ libsbiutils-objs-$(CONFIG_FDT_CPPC) += cppc/fdt_cppc_drivers.carray.o
 
 carray-fdt_cppc_drivers-$(CONFIG_FDT_CPPC_RPMI) += fdt_cppc_rpmi
 libsbiutils-objs-$(CONFIG_FDT_CPPC_RPMI) += cppc/fdt_cppc_rpmi.o
+
+carray-fdt_cppc_drivers-$(CONFIG_FDT_CPPC_SG2044) += fdt_cppc_sg2044
+libsbiutils-objs-$(CONFIG_FDT_CPPC_SG2044) += cppc/fdt_cppc_sg2044.o