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authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-21 12:32:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-21 12:32:42 -0700
commitf22c5579a7d600fa03f8c1d150cf78188f8709b6 (patch)
tree9865bd0b054c4407029bbb1d411b14091fc8d9bf
parentc0a4f5b354dc26573cfaa541064fd35a794eb166 (diff)
parentfc26f5bbf19459930b7290c87b65a9ae6a274650 (diff)
Merge tag 'riscv-for-linus-5.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt: - The CLINT driver has been split in two: one to handle the M-mode CLINT (memory mapped and used on NOMMU systems) and one to handle the S-mode CLINT (via SBI). - The addition of SiFive's drivers to rv32_defconfig * tag 'riscv-for-linus-5.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Add SiFive drivers to rv32_defconfig dt-bindings: timer: Add CLINT bindings RISC-V: Remove CLINT related code from timer and arch clocksource/drivers: Add CLINT timer driver RISC-V: Add mechanism to provide custom IPI operations
-rw-r--r--Documentation/devicetree/bindings/timer/sifive,clint.yaml60
-rw-r--r--arch/riscv/Kconfig2
-rw-r--r--arch/riscv/Kconfig.socs2
-rw-r--r--arch/riscv/configs/nommu_virt_defconfig7
-rw-r--r--arch/riscv/configs/rv32_defconfig5
-rw-r--r--arch/riscv/include/asm/clint.h39
-rw-r--r--arch/riscv/include/asm/smp.h19
-rw-r--r--arch/riscv/include/asm/timex.h28
-rw-r--r--arch/riscv/kernel/Makefile2
-rw-r--r--arch/riscv/kernel/clint.c44
-rw-r--r--arch/riscv/kernel/sbi.c14
-rw-r--r--arch/riscv/kernel/setup.c2
-rw-r--r--arch/riscv/kernel/smp.c44
-rw-r--r--arch/riscv/kernel/smpboot.c4
-rw-r--r--drivers/clocksource/Kconfig12
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/timer-clint.c226
-rw-r--r--drivers/clocksource/timer-riscv.c17
-rw-r--r--include/linux/cpuhotplug.h1
19 files changed, 376 insertions, 153 deletions
diff --git a/Documentation/devicetree/bindings/timer/sifive,clint.yaml b/Documentation/devicetree/bindings/timer/sifive,clint.yaml
new file mode 100644
index 000000000000..2a0e9cd9fbcf
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/sifive,clint.yaml
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/sifive,clint.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive Core Local Interruptor
+
+maintainers:
+ - Palmer Dabbelt <palmer@dabbelt.com>
+ - Anup Patel <anup.patel@wdc.com>
+
+description:
+ SiFive (and other RISC-V) SOCs include an implementation of the SiFive
+ Core Local Interruptor (CLINT) for M-mode timer and M-mode inter-processor
+ interrupts. It directly connects to the timer and inter-processor interrupt
+ lines of various HARTs (or CPUs) so RISC-V per-HART (or per-CPU) local
+ interrupt controller is the parent interrupt controller for CLINT device.
+ The clock frequency of CLINT is specified via "timebase-frequency" DT
+ property of "/cpus" DT node. The "timebase-frequency" DT property is
+ described in Documentation/devicetree/bindings/riscv/cpus.yaml
+
+properties:
+ compatible:
+ items:
+ - const: sifive,fu540-c000-clint
+ - const: sifive,clint0
+
+ description:
+ Should be "sifive,<chip>-clint" and "sifive,clint<version>".
+ Supported compatible strings are -
+ "sifive,fu540-c000-clint" for the SiFive CLINT v0 as integrated
+ onto the SiFive FU540 chip, and "sifive,clint0" for the SiFive
+ CLINT v0 IP block with no chip integration tweaks.
+ Please refer to sifive-blocks-ip-versioning.txt for details
+
+ reg:
+ maxItems: 1
+
+ interrupts-extended:
+ minItems: 1
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - interrupts-extended
+
+examples:
+ - |
+ timer@2000000 {
+ compatible = "sifive,fu540-c000-clint", "sifive,clint0";
+ interrupts-extended = <&cpu1intc 3 &cpu1intc 7
+ &cpu2intc 3 &cpu2intc 7
+ &cpu3intc 3 &cpu3intc 7
+ &cpu4intc 3 &cpu4intc 7>;
+ reg = <0x2000000 0x10000>;
+ };
+...
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 7b5905529146..df18372861d8 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -81,7 +81,7 @@ config RISCV
select PCI_DOMAINS_GENERIC if PCI
select PCI_MSI if PCI
select RISCV_INTC
- select RISCV_TIMER
+ select RISCV_TIMER if RISCV_SBI
select SPARSEMEM_STATIC if 32BIT
select SPARSE_IRQ
select SYSCTL_EXCEPTION_TRACE
diff --git a/arch/riscv/Kconfig.socs b/arch/riscv/Kconfig.socs
index 6c88148f1b9b..8a55f6156661 100644
--- a/arch/riscv/Kconfig.socs
+++ b/arch/riscv/Kconfig.socs
@@ -12,6 +12,7 @@ config SOC_SIFIVE
config SOC_VIRT
bool "QEMU Virt Machine"
+ select CLINT_TIMER if RISCV_M_MODE
select POWER_RESET
select POWER_RESET_SYSCON
select POWER_RESET_SYSCON_POWEROFF
@@ -24,6 +25,7 @@ config SOC_VIRT
config SOC_KENDRYTE
bool "Kendryte K210 SoC"
depends on !MMU
+ select CLINT_TIMER if RISCV_M_MODE
select SERIAL_SIFIVE if TTY
select SERIAL_SIFIVE_CONSOLE if TTY
select SIFIVE_PLIC
diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
index f27596e9663e..e046a0babde4 100644
--- a/arch/riscv/configs/nommu_virt_defconfig
+++ b/arch/riscv/configs/nommu_virt_defconfig
@@ -26,6 +26,7 @@ CONFIG_EXPERT=y
CONFIG_SLOB=y
# CONFIG_SLAB_MERGE_DEFAULT is not set
# CONFIG_MMU is not set
+CONFIG_SOC_VIRT=y
CONFIG_MAXPHYSMEM_2GB=y
CONFIG_SMP=y
CONFIG_CMDLINE="root=/dev/vda rw earlycon=uart8250,mmio,0x10000000,115200n8 console=ttyS0"
@@ -49,7 +50,6 @@ CONFIG_VIRTIO_BLK=y
# CONFIG_SERIO is not set
# CONFIG_LEGACY_PTYS is not set
# CONFIG_LDISC_AUTOLOAD is not set
-# CONFIG_DEVMEM is not set
CONFIG_SERIAL_8250=y
# CONFIG_SERIAL_8250_DEPRECATED_OPTIONS is not set
CONFIG_SERIAL_8250_CONSOLE=y
@@ -57,16 +57,13 @@ CONFIG_SERIAL_8250_NR_UARTS=1
CONFIG_SERIAL_8250_RUNTIME_UARTS=1
CONFIG_SERIAL_OF_PLATFORM=y
# CONFIG_HW_RANDOM is not set
+# CONFIG_DEVMEM is not set
# CONFIG_HWMON is not set
-# CONFIG_LCD_CLASS_DEVICE is not set
-# CONFIG_BACKLIGHT_CLASS_DEVICE is not set
# CONFIG_VGA_CONSOLE is not set
# CONFIG_HID is not set
# CONFIG_USB_SUPPORT is not set
CONFIG_VIRTIO_MMIO=y
CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES=y
-CONFIG_SIFIVE_PLIC=y
-# CONFIG_VALIDATE_FS_PARSER is not set
CONFIG_EXT2_FS=y
# CONFIG_DNOTIFY is not set
# CONFIG_INOTIFY_USER is not set
diff --git a/arch/riscv/configs/rv32_defconfig b/arch/riscv/configs/rv32_defconfig
index 3a55f0e00d6c..2c2cda6cc1c5 100644
--- a/arch/riscv/configs/rv32_defconfig
+++ b/arch/riscv/configs/rv32_defconfig
@@ -14,6 +14,7 @@ CONFIG_CHECKPOINT_RESTORE=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_EXPERT=y
CONFIG_BPF_SYSCALL=y
+CONFIG_SOC_SIFIVE=y
CONFIG_SOC_VIRT=y
CONFIG_ARCH_RV32I=y
CONFIG_SMP=y
@@ -62,6 +63,8 @@ CONFIG_HVC_RISCV_SBI=y
CONFIG_VIRTIO_CONSOLE=y
CONFIG_HW_RANDOM=y
CONFIG_HW_RANDOM_VIRTIO=y
+CONFIG_SPI=y
+CONFIG_SPI_SIFIVE=y
# CONFIG_PTP_1588_CLOCK is not set
CONFIG_POWER_RESET=y
CONFIG_DRM=y
@@ -77,6 +80,8 @@ CONFIG_USB_OHCI_HCD=y
CONFIG_USB_OHCI_HCD_PLATFORM=y
CONFIG_USB_STORAGE=y
CONFIG_USB_UAS=y
+CONFIG_MMC=y
+CONFIG_MMC_SPI=y
CONFIG_RTC_CLASS=y
CONFIG_VIRTIO_PCI=y
CONFIG_VIRTIO_BALLOON=y
diff --git a/arch/riscv/include/asm/clint.h b/arch/riscv/include/asm/clint.h
deleted file mode 100644
index a279b17a6aad..000000000000
--- a/arch/riscv/include/asm/clint.h
+++ /dev/null
@@ -1,39 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_RISCV_CLINT_H
-#define _ASM_RISCV_CLINT_H 1
-
-#include <linux/io.h>
-#include <linux/smp.h>
-
-#ifdef CONFIG_RISCV_M_MODE
-extern u32 __iomem *clint_ipi_base;
-
-void clint_init_boot_cpu(void);
-
-static inline void clint_send_ipi_single(unsigned long hartid)
-{
- writel(1, clint_ipi_base + hartid);
-}
-
-static inline void clint_send_ipi_mask(const struct cpumask *mask)
-{
- int cpu;
-
- for_each_cpu(cpu, mask)
- clint_send_ipi_single(cpuid_to_hartid_map(cpu));
-}
-
-static inline void clint_clear_ipi(unsigned long hartid)
-{
- writel(0, clint_ipi_base + hartid);
-}
-#else /* CONFIG_RISCV_M_MODE */
-#define clint_init_boot_cpu() do { } while (0)
-
-/* stubs to for code is only reachable under IS_ENABLED(CONFIG_RISCV_M_MODE): */
-void clint_send_ipi_single(unsigned long hartid);
-void clint_send_ipi_mask(const struct cpumask *hartid_mask);
-void clint_clear_ipi(unsigned long hartid);
-#endif /* CONFIG_RISCV_M_MODE */
-
-#endif /* _ASM_RISCV_CLINT_H */
diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index 6dfd2a1446d5..df1f7c4cd433 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -15,6 +15,11 @@
struct seq_file;
extern unsigned long boot_cpu_hartid;
+struct riscv_ipi_ops {
+ void (*ipi_inject)(const struct cpumask *target);
+ void (*ipi_clear)(void);
+};
+
#ifdef CONFIG_SMP
/*
* Mapping between linux logical cpu index and hartid.
@@ -40,6 +45,12 @@ void arch_send_call_function_single_ipi(int cpu);
int riscv_hartid_to_cpuid(int hartid);
void riscv_cpuid_to_hartid_mask(const struct cpumask *in, struct cpumask *out);
+/* Set custom IPI operations */
+void riscv_set_ipi_ops(struct riscv_ipi_ops *ops);
+
+/* Clear IPI for current CPU */
+void riscv_clear_ipi(void);
+
/* Secondary hart entry */
asmlinkage void smp_callin(void);
@@ -81,6 +92,14 @@ static inline void riscv_cpuid_to_hartid_mask(const struct cpumask *in,
cpumask_set_cpu(boot_cpu_hartid, out);
}
+static inline void riscv_set_ipi_ops(struct riscv_ipi_ops *ops)
+{
+}
+
+static inline void riscv_clear_ipi(void)
+{
+}
+
#endif /* CONFIG_SMP */
#if defined(CONFIG_HOTPLUG_CPU) && (CONFIG_SMP)
diff --git a/arch/riscv/include/asm/timex.h b/arch/riscv/include/asm/timex.h
index bad2a7c2cda5..a3fb85d505d4 100644
--- a/arch/riscv/include/asm/timex.h
+++ b/arch/riscv/include/asm/timex.h
@@ -7,41 +7,27 @@
#define _ASM_RISCV_TIMEX_H
#include <asm/csr.h>
-#include <asm/mmio.h>
typedef unsigned long cycles_t;
-extern u64 __iomem *riscv_time_val;
-extern u64 __iomem *riscv_time_cmp;
-
-#ifdef CONFIG_64BIT
-#define mmio_get_cycles() readq_relaxed(riscv_time_val)
-#else
-#define mmio_get_cycles() readl_relaxed(riscv_time_val)
-#define mmio_get_cycles_hi() readl_relaxed(((u32 *)riscv_time_val) + 1)
-#endif
-
static inline cycles_t get_cycles(void)
{
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- return csr_read(CSR_TIME);
- return mmio_get_cycles();
+ return csr_read(CSR_TIME);
}
#define get_cycles get_cycles
+static inline u32 get_cycles_hi(void)
+{
+ return csr_read(CSR_TIMEH);
+}
+#define get_cycles_hi get_cycles_hi
+
#ifdef CONFIG_64BIT
static inline u64 get_cycles64(void)
{
return get_cycles();
}
#else /* CONFIG_64BIT */
-static inline u32 get_cycles_hi(void)
-{
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- return csr_read(CSR_TIMEH);
- return mmio_get_cycles_hi();
-}
-
static inline u64 get_cycles64(void)
{
u32 hi, lo;
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index a5287ab9f7f2..dc93710f0b2f 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -31,7 +31,7 @@ obj-y += cacheinfo.o
obj-y += patch.o
obj-$(CONFIG_MMU) += vdso.o vdso/
-obj-$(CONFIG_RISCV_M_MODE) += clint.o traps_misaligned.o
+obj-$(CONFIG_RISCV_M_MODE) += traps_misaligned.o
obj-$(CONFIG_FPU) += fpu.o
obj-$(CONFIG_SMP) += smpboot.o
obj-$(CONFIG_SMP) += smp.o
diff --git a/arch/riscv/kernel/clint.c b/arch/riscv/kernel/clint.c
deleted file mode 100644
index 3647980d14c3..000000000000
--- a/arch/riscv/kernel/clint.c
+++ /dev/null
@@ -1,44 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2019 Christoph Hellwig.
- */
-
-#include <linux/io.h>
-#include <linux/of_address.h>
-#include <linux/types.h>
-#include <asm/clint.h>
-#include <asm/csr.h>
-#include <asm/timex.h>
-#include <asm/smp.h>
-
-/*
- * This is the layout used by the SiFive clint, which is also shared by the qemu
- * virt platform, and the Kendryte KD210 at least.
- */
-#define CLINT_IPI_OFF 0
-#define CLINT_TIME_CMP_OFF 0x4000
-#define CLINT_TIME_VAL_OFF 0xbff8
-
-u32 __iomem *clint_ipi_base;
-
-void clint_init_boot_cpu(void)
-{
- struct device_node *np;
- void __iomem *base;
-
- np = of_find_compatible_node(NULL, NULL, "riscv,clint0");
- if (!np) {
- panic("clint not found");
- return;
- }
-
- base = of_iomap(np, 0);
- if (!base)
- panic("could not map CLINT");
-
- clint_ipi_base = base + CLINT_IPI_OFF;
- riscv_time_cmp = base + CLINT_TIME_CMP_OFF;
- riscv_time_val = base + CLINT_TIME_VAL_OFF;
-
- clint_clear_ipi(boot_cpu_hartid);
-}
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index f383ef5672b2..226ccce0f9e0 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -547,6 +547,18 @@ static inline long sbi_get_firmware_version(void)
return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_VERSION);
}
+static void sbi_send_cpumask_ipi(const struct cpumask *target)
+{
+ struct cpumask hartid_mask;
+
+ riscv_cpuid_to_hartid_mask(target, &hartid_mask);
+
+ sbi_send_ipi(cpumask_bits(&hartid_mask));
+}
+
+static struct riscv_ipi_ops sbi_ipi_ops = {
+ .ipi_inject = sbi_send_cpumask_ipi
+};
int __init sbi_init(void)
{
@@ -587,5 +599,7 @@ int __init sbi_init(void)
__sbi_rfence = __sbi_rfence_v01;
}
+ riscv_set_ipi_ops(&sbi_ipi_ops);
+
return 0;
}
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index f04373be54a6..2c6dd329312b 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -18,7 +18,6 @@
#include <linux/swiotlb.h>
#include <linux/smp.h>
-#include <asm/clint.h>
#include <asm/cpu_ops.h>
#include <asm/setup.h>
#include <asm/sections.h>
@@ -79,7 +78,6 @@ void __init setup_arch(char **cmdline_p)
#else
unflatten_device_tree();
#endif
- clint_init_boot_cpu();
#ifdef CONFIG_SWIOTLB
swiotlb_init(1);
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 554b0fb47060..ea028d9e0d24 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -18,7 +18,6 @@
#include <linux/delay.h>
#include <linux/irq_work.h>
-#include <asm/clint.h>
#include <asm/sbi.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
@@ -86,9 +85,25 @@ static void ipi_stop(void)
wait_for_interrupt();
}
+static struct riscv_ipi_ops *ipi_ops;
+
+void riscv_set_ipi_ops(struct riscv_ipi_ops *ops)
+{
+ ipi_ops = ops;
+}
+EXPORT_SYMBOL_GPL(riscv_set_ipi_ops);
+
+void riscv_clear_ipi(void)
+{
+ if (ipi_ops && ipi_ops->ipi_clear)
+ ipi_ops->ipi_clear();
+
+ csr_clear(CSR_IP, IE_SIE);
+}
+EXPORT_SYMBOL_GPL(riscv_clear_ipi);
+
static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
{
- struct cpumask hartid_mask;
int cpu;
smp_mb__before_atomic();
@@ -96,33 +111,22 @@ static void send_ipi_mask(const struct cpumask *mask, enum ipi_message_type op)
set_bit(op, &ipi_data[cpu].bits);
smp_mb__after_atomic();
- riscv_cpuid_to_hartid_mask(mask, &hartid_mask);
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- sbi_send_ipi(cpumask_bits(&hartid_mask));
+ if (ipi_ops && ipi_ops->ipi_inject)
+ ipi_ops->ipi_inject(mask);
else
- clint_send_ipi_mask(mask);
+ pr_warn("SMP: IPI inject method not available\n");
}
static void send_ipi_single(int cpu, enum ipi_message_type op)
{
- int hartid = cpuid_to_hartid_map(cpu);
-
smp_mb__before_atomic();
set_bit(op, &ipi_data[cpu].bits);
smp_mb__after_atomic();
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- sbi_send_ipi(cpumask_bits(cpumask_of(hartid)));
- else
- clint_send_ipi_single(hartid);
-}
-
-static inline void clear_ipi(void)
-{
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- csr_clear(CSR_IP, IE_SIE);
+ if (ipi_ops && ipi_ops->ipi_inject)
+ ipi_ops->ipi_inject(cpumask_of(cpu));
else
- clint_clear_ipi(cpuid_to_hartid_map(smp_processor_id()));
+ pr_warn("SMP: IPI inject method not available\n");
}
#ifdef CONFIG_IRQ_WORK
@@ -140,7 +144,7 @@ void handle_IPI(struct pt_regs *regs)
irq_enter();
- clear_ipi();
+ riscv_clear_ipi();
while (true) {
unsigned long ops;
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 356825a57551..96167d55ed98 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -24,7 +24,6 @@
#include <linux/of.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/mm.h>
-#include <asm/clint.h>
#include <asm/cpu_ops.h>
#include <asm/irq.h>
#include <asm/mmu_context.h>
@@ -147,8 +146,7 @@ asmlinkage __visible void smp_callin(void)
struct mm_struct *mm = &init_mm;
unsigned int curr_cpuid = smp_processor_id();
- if (!IS_ENABLED(CONFIG_RISCV_SBI))
- clint_clear_ipi(cpuid_to_hartid_map(smp_processor_id()));
+ riscv_clear_ipi();
/* All kernel threads share the same mm context. */
mmgrab(mm);
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 3576ad7bd380..68b087bff59c 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -653,9 +653,8 @@ config ATCPIT100_TIMER
This option enables support for the Andestech ATCPIT100 timers.
config RISCV_TIMER
- bool "Timer for the RISC-V platform"
+ bool "Timer for the RISC-V platform" if COMPILE_TEST
depends on GENERIC_SCHED_CLOCK && RISCV
- default y
select TIMER_PROBE
select TIMER_OF
help
@@ -663,6 +662,15 @@ config RISCV_TIMER
is accessed via both the SBI and the rdcycle instruction. This is
required for all RISC-V systems.
+config CLINT_TIMER
+ bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST
+ depends on GENERIC_SCHED_CLOCK && RISCV
+ select TIMER_PROBE
+ select TIMER_OF
+ help
+ This option enables the CLINT timer for RISC-V systems. The CLINT
+ driver is usually used for NoMMU RISC-V systems.
+
config CSKY_MP_TIMER
bool "SMP Timer for the C-SKY platform" if COMPILE_TEST
depends on CSKY
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index eaedb7240ae7..1c444cc3bb44 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -89,6 +89,7 @@ obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o
obj-$(CONFIG_X86_NUMACHIP) += numachip.o
obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o
obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o
+obj-$(CONFIG_CLINT_TIMER) += timer-clint.o
obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o
obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o
obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o
diff --git a/drivers/clocksource/timer-clint.c b/drivers/clocksource/timer-clint.c
new file mode 100644
index 000000000000..8eeafa82c03d
--- /dev/null
+++ b/drivers/clocksource/timer-clint.c
@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Western Digital Corporation or its affiliates.
+ *
+ * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a
+ * CLINT MMIO timer device.
+ */
+
+#define pr_fmt(fmt) "clint: " fmt
+#include <linux/bitops.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/smp.h>
+
+#define CLINT_IPI_OFF 0
+#define CLINT_TIMER_CMP_OFF 0x4000
+#define CLINT_TIMER_VAL_OFF 0xbff8
+
+/* CLINT manages IPI and Timer for RISC-V M-mode */
+static u32 __iomem *clint_ipi_base;
+static u64 __iomem *clint_timer_cmp;
+static u64 __iomem *clint_timer_val;
+static unsigned long clint_timer_freq;
+static unsigned int clint_timer_irq;
+
+static void clint_send_ipi(const struct cpumask *target)
+{
+ unsigned int cpu;
+
+ for_each_cpu(cpu, target)
+ writel(1, clint_ipi_base + cpuid_to_hartid_map(cpu));
+}
+
+static void clint_clear_ipi(void)
+{
+ writel(0, clint_ipi_base + cpuid_to_hartid_map(smp_processor_id()));
+}
+
+static struct riscv_ipi_ops clint_ipi_ops = {
+ .ipi_inject = clint_send_ipi,
+ .ipi_clear = clint_clear_ipi,
+};
+
+#ifdef CONFIG_64BIT
+#define clint_get_cycles() readq_relaxed(clint_timer_val)
+#else
+#define clint_get_cycles() readl_relaxed(clint_timer_val)
+#define clint_get_cycles_hi() readl_relaxed(((u32 *)clint_timer_val) + 1)
+#endif
+
+#ifdef CONFIG_64BIT
+static u64 notrace clint_get_cycles64(void)
+{
+ return clint_get_cycles();
+}
+#else /* CONFIG_64BIT */
+static u64 notrace clint_get_cycles64(void)
+{
+ u32 hi, lo;
+
+ do {
+ hi = clint_get_cycles_hi();
+ lo = clint_get_cycles();
+ } while (hi != clint_get_cycles_hi());
+
+ return ((u64)hi << 32) | lo;
+}
+#endif /* CONFIG_64BIT */
+
+static u64 clint_rdtime(struct clocksource *cs)
+{
+ return clint_get_cycles64();
+}
+
+static struct clocksource clint_clocksource = {
+ .name = "clint_clocksource",
+ .rating = 300,
+ .mask = CLOCKSOURCE_MASK(64),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .read = clint_rdtime,
+};
+
+static int clint_clock_next_event(unsigned long delta,
+ struct clock_event_device *ce)
+{
+ void __iomem *r = clint_timer_cmp +
+ cpuid_to_hartid_map(smp_processor_id());
+
+ csr_set(CSR_IE, IE_TIE);
+ writeq_relaxed(clint_get_cycles64() + delta, r);
+ return 0;
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, clint_clock_event) = {
+ .name = "clint_clockevent",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 100,
+ .set_next_event = clint_clock_next_event,
+};
+
+static int clint_timer_starting_cpu(unsigned int cpu)
+{
+ struct clock_event_device *ce = per_cpu_ptr(&clint_clock_event, cpu);
+
+ ce->cpumask = cpumask_of(cpu);
+ clockevents_config_and_register(ce, clint_timer_freq, 100, 0x7fffffff);
+
+ enable_percpu_irq(clint_timer_irq,
+ irq_get_trigger_type(clint_timer_irq));
+ return 0;
+}
+
+static int clint_timer_dying_cpu(unsigned int cpu)
+{
+ disable_percpu_irq(clint_timer_irq);
+ return 0;
+}
+
+static irqreturn_t clint_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evdev = this_cpu_ptr(&clint_clock_event);
+
+ csr_clear(CSR_IE, IE_TIE);
+ evdev->event_handler(evdev);
+
+ return IRQ_HANDLED;
+}
+
+static int __init clint_timer_init_dt(struct device_node *np)
+{
+ int rc;
+ u32 i, nr_irqs;
+ void __iomem *base;
+ struct of_phandle_args oirq;
+
+ /*
+ * Ensure that CLINT device interrupts are either RV_IRQ_TIMER or
+ * RV_IRQ_SOFT. If it's anything else then we ignore the device.
+ */
+ nr_irqs = of_irq_count(np);
+ for (i = 0; i < nr_irqs; i++) {
+ if (of_irq_parse_one(np, i, &oirq)) {
+ pr_err("%pOFP: failed to parse irq %d.\n", np, i);
+ continue;
+ }
+
+ if ((oirq.args_count != 1) ||
+ (oirq.args[0] != RV_IRQ_TIMER &&
+ oirq.args[0] != RV_IRQ_SOFT)) {
+ pr_err("%pOFP: invalid irq %d (hwirq %d)\n",
+ np, i, oirq.args[0]);
+ return -ENODEV;
+ }
+
+ /* Find parent irq domain and map timer irq */
+ if (!clint_timer_irq &&
+ oirq.args[0] == RV_IRQ_TIMER &&
+ irq_find_host(oirq.np))
+ clint_timer_irq = irq_of_parse_and_map(np, i);
+ }
+
+ /* If CLINT timer irq not found then fail */
+ if (!clint_timer_irq) {
+ pr_err("%pOFP: timer irq not found\n", np);
+ return -ENODEV;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("%pOFP: could not map registers\n", np);
+ return -ENODEV;
+ }
+
+ clint_ipi_base = base + CLINT_IPI_OFF;
+ clint_timer_cmp = base + CLINT_TIMER_CMP_OFF;
+ clint_timer_val = base + CLINT_TIMER_VAL_OFF;
+ clint_timer_freq = riscv_timebase;
+
+ pr_info("%pOFP: timer running at %ld Hz\n", np, clint_timer_freq);
+
+ rc = clocksource_register_hz(&clint_clocksource, clint_timer_freq);
+ if (rc) {
+ pr_err("%pOFP: clocksource register failed [%d]\n", np, rc);
+ goto fail_iounmap;
+ }
+
+ sched_clock_register(clint_get_cycles64, 64, clint_timer_freq);
+
+ rc = request_percpu_irq(clint_timer_irq, clint_timer_interrupt,
+ "clint-timer", &clint_clock_event);
+ if (rc) {
+ pr_err("registering percpu irq failed [%d]\n", rc);
+ goto fail_iounmap;
+ }
+
+ rc = cpuhp_setup_state(CPUHP_AP_CLINT_TIMER_STARTING,
+ "clockevents/clint/timer:starting",
+ clint_timer_starting_cpu,
+ clint_timer_dying_cpu);
+ if (rc) {
+ pr_err("%pOFP: cpuhp setup state failed [%d]\n", np, rc);
+ goto fail_free_irq;
+ }
+
+ riscv_set_ipi_ops(&clint_ipi_ops);
+ clint_clear_ipi();
+
+ return 0;
+
+fail_free_irq:
+ free_irq(clint_timer_irq, &clint_clock_event);
+fail_iounmap:
+ iounmap(base);
+ return rc;
+}
+
+TIMER_OF_DECLARE(clint_timer, "riscv,clint0", clint_timer_init_dt);
+TIMER_OF_DECLARE(clint_timer1, "sifive,clint0", clint_timer_init_dt);
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 9de1dabfb126..c51c5ed15aa7 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -19,26 +19,13 @@
#include <linux/of_irq.h>
#include <asm/smp.h>
#include <asm/sbi.h>
-
-u64 __iomem *riscv_time_cmp;
-u64 __iomem *riscv_time_val;
-
-static inline void mmio_set_timer(u64 val)
-{
- void __iomem *r;
-
- r = riscv_time_cmp + cpuid_to_hartid_map(smp_processor_id());
- writeq_relaxed(val, r);
-}
+#include <asm/timex.h>
static int riscv_clock_next_event(unsigned long delta,
struct clock_event_device *ce)
{
csr_set(CSR_IE, IE_TIE);
- if (IS_ENABLED(CONFIG_RISCV_SBI))
- sbi_set_timer(get_cycles64() + delta);
- else
- mmio_set_timer(get_cycles64() + delta);
+ sbi_set_timer(get_cycles64() + delta);
return 0;
}
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index a2710e654b64..3215023d4852 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -132,6 +132,7 @@ enum cpuhp_state {
CPUHP_AP_MIPS_GIC_TIMER_STARTING,
CPUHP_AP_ARC_TIMER_STARTING,
CPUHP_AP_RISCV_TIMER_STARTING,
+ CPUHP_AP_CLINT_TIMER_STARTING,
CPUHP_AP_CSKY_TIMER_STARTING,
CPUHP_AP_HYPERV_TIMER_STARTING,
CPUHP_AP_KVM_STARTING,

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