LoongArch: Add suspend (ACPI S3) support
Add suspend (Suspend To RAM, aka ACPI S3) support for LoongArch.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 48db4b2..0c8b2b1 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -56,6 +56,7 @@
select ARCH_WANTS_NO_INSTR
select BUILDTIME_TABLE_SORT
select COMMON_CLK
+ select CPU_PM
select EFI
select GENERIC_CLOCKEVENTS
select GENERIC_CMOS_UPDATE
@@ -517,6 +518,10 @@
menu "Power management options"
+config ARCH_SUSPEND_POSSIBLE
+ def_bool y
+
+source "kernel/power/Kconfig"
source "drivers/acpi/Kconfig"
endmenu
diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
index 01b57b7..5232d8c 100644
--- a/arch/loongarch/Makefile
+++ b/arch/loongarch/Makefile
@@ -104,6 +104,9 @@
libs-y += arch/loongarch/lib/
libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
+# suspend and hibernation support
+drivers-$(CONFIG_PM) += arch/loongarch/power/
+
ifeq ($(KBUILD_EXTMOD),)
prepare: vdso_prepare
vdso_prepare: prepare0
diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h
index 825c251..4198753 100644
--- a/arch/loongarch/include/asm/acpi.h
+++ b/arch/loongarch/include/asm/acpi.h
@@ -35,4 +35,14 @@ extern struct list_head acpi_wakeup_device_list;
#define ACPI_TABLE_UPGRADE_MAX_PHYS ARCH_LOW_ADDRESS_LIMIT
+extern int loongarch_acpi_suspend(void);
+extern int (*acpi_suspend_lowlevel)(void);
+extern void loongarch_suspend_enter(void);
+
+static inline unsigned long acpi_get_wakeup_address(void)
+{
+ extern void loongarch_wakeup_start(void);
+ return (unsigned long)loongarch_wakeup_start;
+}
+
#endif /* _ASM_LOONGARCH_ACPI_H */
diff --git a/arch/loongarch/include/asm/bootinfo.h b/arch/loongarch/include/asm/bootinfo.h
index ed0910e..0051b52 100644
--- a/arch/loongarch/include/asm/bootinfo.h
+++ b/arch/loongarch/include/asm/bootinfo.h
@@ -32,6 +32,7 @@ struct loongson_system_configuration {
int cores_per_node;
int cores_per_package;
unsigned long cores_io_master;
+ unsigned long suspend_addr;
const char *cpuname;
};
diff --git a/arch/loongarch/include/asm/loongson.h b/arch/loongarch/include/asm/loongson.h
index 00db93e..12494cf 100644
--- a/arch/loongarch/include/asm/loongson.h
+++ b/arch/loongarch/include/asm/loongson.h
@@ -136,4 +136,7 @@ typedef enum {
#define ls7a_writel(val, addr) *(volatile unsigned int *)TO_UNCACHE(addr) = (val)
#define ls7a_writeq(val, addr) *(volatile unsigned long *)TO_UNCACHE(addr) = (val)
+void enable_gpe_wakeup(void);
+void enable_pci_wakeup(void);
+
#endif /* __ASM_LOONGSON_H */
diff --git a/arch/loongarch/include/asm/time.h b/arch/loongarch/include/asm/time.h
index 2eae219..037a2d1 100644
--- a/arch/loongarch/include/asm/time.h
+++ b/arch/loongarch/include/asm/time.h
@@ -12,6 +12,7 @@
extern u64 cpu_clock_freq;
extern u64 const_clock_freq;
+extern void save_counter(void);
extern void sync_counter(void);
static inline unsigned int calc_const_freq(void)
diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
index 5a63f85f..98f4311 100644
--- a/arch/loongarch/kernel/acpi.c
+++ b/arch/loongarch/kernel/acpi.c
@@ -140,6 +140,12 @@ static void __init acpi_process_madt(void)
loongson_sysconf.nr_cpus = num_processors;
}
+#ifndef CONFIG_SUSPEND
+int (*acpi_suspend_lowlevel)(void);
+#else
+int (*acpi_suspend_lowlevel)(void) = loongarch_acpi_suspend;
+#endif
+
void __init acpi_boot_table_init(void)
{
/*
diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c
index b78816c..8c6e227 100644
--- a/arch/loongarch/kernel/smp.c
+++ b/arch/loongarch/kernel/smp.c
@@ -16,6 +16,7 @@
#include <linux/smp.h>
#include <linux/threads.h>
#include <linux/export.h>
+#include <linux/syscore_ops.h>
#include <linux/time.h>
#include <linux/tracepoint.h>
#include <linux/sched/hotplug.h>
diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c
index 786735d..a6576de 100644
--- a/arch/loongarch/kernel/time.c
+++ b/arch/loongarch/kernel/time.c
@@ -115,12 +115,17 @@ static unsigned long __init get_loops_per_jiffy(void)
return lpj;
}
-static long init_timeval;
+static long init_offset __nosavedata;
+
+void save_counter(void)
+{
+ init_offset = drdtime();
+}
void sync_counter(void)
{
/* Ensure counter begin at 0 */
- csr_write64(-init_timeval, LOONGARCH_CSR_CNTC);
+ csr_write64(init_offset, LOONGARCH_CSR_CNTC);
}
static int get_timer_irq(void)
@@ -219,7 +224,7 @@ void __init time_init(void)
else
const_clock_freq = calc_const_freq();
- init_timeval = drdtime() - csr_read64(LOONGARCH_CSR_CNTC);
+ init_offset = -(drdtime() - csr_read64(LOONGARCH_CSR_CNTC));
constant_clockevent_init();
constant_clocksource_init();
diff --git a/arch/loongarch/power/Makefile b/arch/loongarch/power/Makefile
new file mode 100644
index 0000000..6740117
--- /dev/null
+++ b/arch/loongarch/power/Makefile
@@ -0,0 +1,3 @@
+obj-y += platform.o
+
+obj-$(CONFIG_SUSPEND) += suspend.o suspend_asm.o
diff --git a/arch/loongarch/power/platform.c b/arch/loongarch/power/platform.c
new file mode 100644
index 0000000..3ea8e07
--- /dev/null
+++ b/arch/loongarch/power/platform.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/acpi.h>
+#include <linux/platform_device.h>
+
+#include <asm/bootinfo.h>
+#include <asm/loongson.h>
+
+void enable_gpe_wakeup(void)
+{
+ if (acpi_disabled)
+ return;
+
+ if (acpi_gbl_reduced_hardware)
+ return;
+
+ acpi_enable_all_wakeup_gpes();
+}
+
+void enable_pci_wakeup(void)
+{
+ if (acpi_disabled)
+ return;
+
+ if (acpi_gbl_reduced_hardware)
+ return;
+
+ acpi_write_bit_register(ACPI_BITREG_PCIEXP_WAKE_STATUS, 1);
+
+ if (acpi_gbl_FADT.flags & ACPI_FADT_PCI_EXPRESS_WAKE)
+ acpi_write_bit_register(ACPI_BITREG_PCIEXP_WAKE_DISABLE, 0);
+}
+
+static int __init loongson3_acpi_suspend_init(void)
+{
+#ifdef CONFIG_ACPI
+ acpi_status status;
+ uint64_t suspend_addr = 0;
+
+ if (acpi_disabled || acpi_gbl_reduced_hardware)
+ return 0;
+
+ acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
+ status = acpi_evaluate_integer(NULL, "\\SADR", NULL, &suspend_addr);
+ if (ACPI_FAILURE(status) || !suspend_addr) {
+ pr_err("ACPI S3 is not support!\n");
+ return -1;
+ }
+ loongson_sysconf.suspend_addr = (u64)phys_to_virt(PHYSADDR(suspend_addr));
+#endif
+ return 0;
+}
+
+device_initcall(loongson3_acpi_suspend_init);
diff --git a/arch/loongarch/power/suspend.c b/arch/loongarch/power/suspend.c
new file mode 100644
index 0000000..5e19733
--- /dev/null
+++ b/arch/loongarch/power/suspend.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * loongson-specific suspend support
+ *
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/acpi.h>
+#include <linux/pm.h>
+#include <linux/suspend.h>
+
+#include <asm/loongarch.h>
+#include <asm/loongson.h>
+#include <asm/setup.h>
+#include <asm/time.h>
+#include <asm/tlbflush.h>
+
+u64 loongarch_suspend_addr;
+
+struct saved_registers {
+ u32 ecfg;
+ u32 euen;
+ u64 pgd;
+ u64 kpgd;
+ u32 pwctl0;
+ u32 pwctl1;
+};
+static struct saved_registers saved_regs;
+
+static void arch_common_suspend(void)
+{
+ save_counter();
+ saved_regs.pgd = csr_read64(LOONGARCH_CSR_PGDL);
+ saved_regs.kpgd = csr_read64(LOONGARCH_CSR_PGDH);
+ saved_regs.pwctl0 = csr_read32(LOONGARCH_CSR_PWCTL0);
+ saved_regs.pwctl1 = csr_read32(LOONGARCH_CSR_PWCTL1);
+ saved_regs.ecfg = csr_read32(LOONGARCH_CSR_ECFG);
+ saved_regs.euen = csr_read32(LOONGARCH_CSR_EUEN);
+
+ loongarch_suspend_addr = loongson_sysconf.suspend_addr;
+}
+
+static void arch_common_resume(void)
+{
+ sync_counter();
+ local_flush_tlb_all();
+ csr_write64(per_cpu_offset(0), PERCPU_BASE_KS);
+ csr_write64(eentry, LOONGARCH_CSR_EENTRY);
+ csr_write64(eentry, LOONGARCH_CSR_MERRENTRY);
+ csr_write64(tlbrentry, LOONGARCH_CSR_TLBRENTRY);
+
+ csr_write64(saved_regs.pgd, LOONGARCH_CSR_PGDL);
+ csr_write64(saved_regs.kpgd, LOONGARCH_CSR_PGDH);
+ csr_write32(saved_regs.pwctl0, LOONGARCH_CSR_PWCTL0);
+ csr_write32(saved_regs.pwctl1, LOONGARCH_CSR_PWCTL1);
+ csr_write32(saved_regs.ecfg, LOONGARCH_CSR_ECFG);
+ csr_write32(saved_regs.euen, LOONGARCH_CSR_EUEN);
+}
+
+int loongarch_acpi_suspend(void)
+{
+ enable_gpe_wakeup();
+ enable_pci_wakeup();
+
+ arch_common_suspend();
+
+ /* processor specific suspend */
+ loongarch_suspend_enter();
+
+ arch_common_resume();
+
+ return 0;
+}
diff --git a/arch/loongarch/power/suspend_asm.S b/arch/loongarch/power/suspend_asm.S
new file mode 100644
index 0000000..eb26756
--- /dev/null
+++ b/arch/loongarch/power/suspend_asm.S
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Sleep helper for Loongson-3 sleep mode.
+ *
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/addrspace.h>
+#include <asm/loongarch.h>
+#include <asm/stackframe.h>
+
+/* preparatory stuff */
+.macro SETUP_SLEEP
+ addi.d sp, sp, -PT_SIZE
+ st.d $r1, sp, PT_R1
+ st.d $r2, sp, PT_R2
+ st.d $r3, sp, PT_R3
+ st.d $r4, sp, PT_R4
+ st.d $r21, sp, PT_R21
+ st.d $r22, sp, PT_R22
+ st.d $r23, sp, PT_R23
+ st.d $r24, sp, PT_R24
+ st.d $r25, sp, PT_R25
+ st.d $r26, sp, PT_R26
+ st.d $r27, sp, PT_R27
+ st.d $r28, sp, PT_R28
+ st.d $r29, sp, PT_R29
+ st.d $r30, sp, PT_R30
+ st.d $r31, sp, PT_R31
+
+ la.pcrel t0, acpi_saved_sp
+ st.d sp, t0, 0
+.endm
+
+.macro SETUP_WAKEUP
+ ld.d $r1, sp, PT_R1
+ ld.d $r2, sp, PT_R2
+ ld.d $r3, sp, PT_R3
+ ld.d $r4, sp, PT_R4
+ ld.d $r21, sp, PT_R21
+ ld.d $r22, sp, PT_R22
+ ld.d $r23, sp, PT_R23
+ ld.d $r24, sp, PT_R24
+ ld.d $r25, sp, PT_R25
+ ld.d $r26, sp, PT_R26
+ ld.d $r27, sp, PT_R27
+ ld.d $r28, sp, PT_R28
+ ld.d $r29, sp, PT_R29
+ ld.d $r30, sp, PT_R30
+ ld.d $r31, sp, PT_R31
+.endm
+
+ .text
+ .align 12
+
+/* Sleep/wakeup code for Loongson-3 */
+SYM_FUNC_START(loongarch_suspend_enter)
+ SETUP_SLEEP
+ bl __flush_cache_all
+
+ /* Pass RA and SP to BIOS */
+ addi.d a1, sp, 0
+ la.pcrel a0, loongarch_wakeup_start
+ la.pcrel t0, loongarch_suspend_addr
+ ld.d t0, t0, 0
+ jirl a0, t0, 0 /* Call BIOS's STR sleep routine */
+
+ /*
+ * This is where we return upon wakeup.
+ * Reload all of the registers and return.
+ */
+SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
+ li.d t0, CSR_DMW0_INIT # UC, PLV0
+ csrwr t0, LOONGARCH_CSR_DMWIN0
+ li.d t0, CSR_DMW1_INIT # CA, PLV0
+ csrwr t0, LOONGARCH_CSR_DMWIN1
+
+ la.abs t0, 0f
+ jr t0
+0:
+ la.pcrel t0, acpi_saved_sp
+ ld.d sp, t0, 0
+ SETUP_WAKEUP
+ addi.d sp, sp, PT_SIZE
+ jr ra
+SYM_FUNC_END(loongarch_suspend_enter)
