diff options
Diffstat (limited to '')
-rw-r--r-- | arch/riscv/include/asm/clint.h | 57 |
1 files changed, 22 insertions, 35 deletions
diff --git a/arch/riscv/include/asm/clint.h b/arch/riscv/include/asm/clint.h index a279b17a6aad..0789fd37b40a 100644 --- a/arch/riscv/include/asm/clint.h +++ b/arch/riscv/include/asm/clint.h @@ -1,39 +1,26 @@ -/* SPDX-License-Identifier: GPL-2.0 */ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 Google, Inc + */ + #ifndef _ASM_RISCV_CLINT_H -#define _ASM_RISCV_CLINT_H 1 +#define _ASM_RISCV_CLINT_H -#include <linux/io.h> -#include <linux/smp.h> +#include <linux/types.h> +#include <asm/mmio.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 */ +/* + * This lives in the CLINT driver, but is accessed directly by timex.h to avoid + * any overhead when accessing the MMIO timer. + * + * The ISA defines mtime as a 64-bit memory-mapped register that increments at + * a constant frequency, but it doesn't define some other constraints we depend + * on (most notably ordering constraints, but also some simpler stuff like the + * memory layout). Thus, this is called "clint_time_val" instead of something + * like "riscv_mtime", to signify that these non-ISA assumptions must hold. + */ +extern u64 __iomem *clint_time_val; +#endif + +#endif |