[PATCH v9 1/3] MIPS: Loongson64: Add Loongson-2K1000 reset platform driver

From: Qing Zhang
Date: Thu Nov 25 2021 - 20:54:40 EST


Add power management register operations to support reboot and poweroff.

Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
---
v8-v9:
No change
---
drivers/platform/mips/Kconfig | 6 ++++
drivers/platform/mips/Makefile | 1 +
drivers/platform/mips/ls2k-reset.c | 53 ++++++++++++++++++++++++++++++
3 files changed, 60 insertions(+)
create mode 100644 drivers/platform/mips/ls2k-reset.c

diff --git a/drivers/platform/mips/Kconfig b/drivers/platform/mips/Kconfig
index 8ac149173c64b..d421e14823957 100644
--- a/drivers/platform/mips/Kconfig
+++ b/drivers/platform/mips/Kconfig
@@ -30,4 +30,10 @@ config RS780E_ACPI
help
Loongson RS780E PCH ACPI Controller driver.

+config LS2K_RESET
+ bool "Loongson-2K1000 Reset Controller"
+ depends on MACH_LOONGSON64 || COMPILE_TEST
+ help
+ Loongson-2K1000 Reset Controller driver.
+
endif # MIPS_PLATFORM_DEVICES
diff --git a/drivers/platform/mips/Makefile b/drivers/platform/mips/Makefile
index 1781490987773..4c71444e453a6 100644
--- a/drivers/platform/mips/Makefile
+++ b/drivers/platform/mips/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_CPU_HWMON) += cpu_hwmon.o
obj-$(CONFIG_RS780E_ACPI) += rs780e-acpi.o
+obj-$(CONFIG_LS2K_RESET) += ls2k-reset.o
diff --git a/drivers/platform/mips/ls2k-reset.c b/drivers/platform/mips/ls2k-reset.c
new file mode 100644
index 0000000000000..b70e7b8a092c2
--- /dev/null
+++ b/drivers/platform/mips/ls2k-reset.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021, Qing Zhang <zhangqing@xxxxxxxxxxx>
+ * Loongson-2K1000 reset support
+ */
+
+#include <linux/of_address.h>
+#include <linux/pm.h>
+#include <asm/reboot.h>
+
+#define PM1_STS 0x0c /* Power Management 1 Status Register */
+#define PM1_CNT 0x14 /* Power Management 1 Control Register */
+#define RST_CNT 0x30 /* Reset Control Register */
+
+static void __iomem *base;
+
+static void ls2k_restart(char *command)
+{
+ writel(0x1, base + RST_CNT);
+}
+
+static void ls2k_poweroff(void)
+{
+ /* Clear */
+ writel((readl(base + PM1_STS) & 0xffffffff), base + PM1_STS);
+ /* Sleep Enable | Soft Off*/
+ writel(GENMASK(12, 10) | BIT(13), base + PM1_CNT);
+}
+
+static int ls2k_reset_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "loongson,ls2k-pm");
+ if (!np) {
+ pr_info("Failed to get PM node\n");
+ return -ENODEV;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_info("Failed to map PM register base address\n");
+ return -ENOMEM;
+ }
+
+ _machine_restart = ls2k_restart;
+ pm_power_off = ls2k_poweroff;
+
+ of_node_put(np);
+ return 0;
+}
+
+arch_initcall(ls2k_reset_init);
--
2.31.0