From: Rick Chen rick@andestech.com
The platform-Level Machine Timer (PLMT) block holds memory-mapped mtime register associated with timer tick.
This driver implements the riscv_get_time() which is required by the generic RISC-V timer driver.
Signed-off-by: Rick Chen rick@andestech.com Cc: Greentime Hu greentime@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- V3: - Add a space before (PLMT).
arch/riscv/Kconfig | 9 ++++++ arch/riscv/include/asm/global_data.h | 3 ++ arch/riscv/include/asm/syscon.h | 1 + arch/riscv/lib/Makefile | 1 + arch/riscv/lib/andes_plmt.c | 53 ++++++++++++++++++++++++++++++++++++ 5 files changed, 67 insertions(+) create mode 100644 arch/riscv/lib/andes_plmt.c
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 511768b..ae8ff7b 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -118,6 +118,15 @@ config ANDES_PLIC The Andes PLIC block holds memory-mapped claim and pending registers associated with software interrupt.
+config ANDES_PLMT + bool + depends on RISCV_MMODE + select REGMAP + select SYSCON + help + The Andes PLMT block holds memory-mapped mtime register + associated with timer tick. + config RISCV_RDTIME bool default y if RISCV_SMODE diff --git a/arch/riscv/include/asm/global_data.h b/arch/riscv/include/asm/global_data.h index b867910..dffcd45 100644 --- a/arch/riscv/include/asm/global_data.h +++ b/arch/riscv/include/asm/global_data.h @@ -21,6 +21,9 @@ struct arch_global_data { #ifdef CONFIG_ANDES_PLIC void __iomem *plic; /* plic base address */ #endif +#ifdef CONFIG_ANDES_PLMT + void __iomem *plmt; /* plmt base address */ +#endif #ifdef CONFIG_SMP struct ipi_data ipi[CONFIG_NR_CPUS]; #endif diff --git a/arch/riscv/include/asm/syscon.h b/arch/riscv/include/asm/syscon.h index c1b4b86..6e12574 100644 --- a/arch/riscv/include/asm/syscon.h +++ b/arch/riscv/include/asm/syscon.h @@ -14,6 +14,7 @@ enum { RISCV_NONE, RISCV_SYSCON_CLINT, /* Core Local Interruptor (CLINT) */ RISCV_SYSCON_PLIC, /* Platform Level Interrupt Controller (PLIC) */ + RISCV_SYSCON_PLMT, /* Platform Level Machine Timer (PLMT) */ };
#endif /* _ASM_SYSCON_H */ diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index 1bf554b..1c332db 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -12,6 +12,7 @@ obj-y += cache.o obj-$(CONFIG_RISCV_RDTIME) += rdtime.o obj-$(CONFIG_SIFIVE_CLINT) += sifive_clint.o obj-$(CONFIG_ANDES_PLIC) += andes_plic.o +obj-$(CONFIG_ANDES_PLMT) += andes_plmt.o obj-y += interrupts.o obj-y += reset.o obj-$(CONFIG_SBI_IPI) += sbi_ipi.o diff --git a/arch/riscv/lib/andes_plmt.c b/arch/riscv/lib/andes_plmt.c new file mode 100644 index 0000000..12d7e0e --- /dev/null +++ b/arch/riscv/lib/andes_plmt.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2019, Rick Chen rick@andestech.com + * + * U-Boot syscon driver for Andes's Platform Level Machine Timer (PLMT). + * The PLMT block holds memory-mapped mtime register + * associated with timer tick. + */ + +#include <common.h> +#include <dm.h> +#include <regmap.h> +#include <syscon.h> +#include <asm/io.h> +#include <asm/syscon.h> + +/* mtime register */ +#define MTIME_REG(base) ((ulong)(base)) + +DECLARE_GLOBAL_DATA_PTR; + +#define PLMT_BASE_GET(void) \ + do { \ + long *ret; \ + \ + if (!gd->arch.plmt) { \ + ret = syscon_get_first_range(RISCV_SYSCON_PLMT); \ + if (IS_ERR(ret)) \ + return PTR_ERR(ret); \ + gd->arch.plmt = ret; \ + } \ + } while (0) + +int riscv_get_time(u64 *time) +{ + PLMT_BASE_GET(); + + *time = readq((void __iomem *)MTIME_REG(gd->arch.plmt)); + + return 0; +} + +static const struct udevice_id nds_plmt_ids[] = { + { .compatible = "riscv,plmt0", .data = RISCV_SYSCON_PLMT }, + { } +}; + +U_BOOT_DRIVER(nds_plmt) = { + .name = "nds_plmt", + .id = UCLASS_SYSCON, + .of_match = nds_plmt_ids, + .flags = DM_FLAG_PRE_RELOC, +};