From 199b75f58a0ffc2ad0871eb4853ca425c78b4893 Mon Sep 17 00:00:00 2001 From: Philipp Hug Date: Thu, 13 Sep 2018 18:11:56 +0200 Subject: [PATCH] arch/riscv: provide a monotonic timer The RISC-V Privileged Architecture specification defines the Machine Time Registers (mtime and mtimecmp) in section 3.1.15. Makes it possible to use the generic udelay. The timer is enabled using RISCV_USE_ARCH_TIMER for the lowrisc, sifive and ucb soc. Change-Id: I5139601226e6f89da69e302a10f2fb56b4b24f38 Signed-off-by: Philipp Hug Reviewed-on: https://review.coreboot.org/27434 Reviewed-by: Ronald G. Minnich Tested-by: build bot (Jenkins) --- src/arch/riscv/Kconfig | 4 ++++ src/arch/riscv/Makefile.inc | 6 ++++++ src/arch/riscv/arch_timer.c | 28 ++++++++++++++++++++++++++++ src/arch/riscv/include/arch/io.h | 10 ++++++++++ src/arch/riscv/misc.c | 4 ---- src/soc/lowrisc/lowrisc/Kconfig | 3 +++ src/soc/sifive/fu540/Kconfig | 4 ++++ src/soc/ucb/riscv/Kconfig | 3 +++ 8 files changed, 58 insertions(+), 4 deletions(-) create mode 100644 src/arch/riscv/arch_timer.c diff --git a/src/arch/riscv/Kconfig b/src/arch/riscv/Kconfig index 916e269b32..2d53f422c1 100644 --- a/src/arch/riscv/Kconfig +++ b/src/arch/riscv/Kconfig @@ -28,3 +28,7 @@ config ARCH_ROMSTAGE_RISCV config ARCH_RAMSTAGE_RISCV bool default n + +config RISCV_USE_ARCH_TIMER + bool + default n diff --git a/src/arch/riscv/Makefile.inc b/src/arch/riscv/Makefile.inc index f4b69bb95e..50c1ae69d6 100644 --- a/src/arch/riscv/Makefile.inc +++ b/src/arch/riscv/Makefile.inc @@ -56,6 +56,8 @@ bootblock-y += \ $(top)/src/lib/memmove.c \ $(top)/src/lib/memset.c +bootblock-$(CONFIG_RISCV_USE_ARCH_TIMER) += arch_timer.c + $(objcbfs)/bootblock.debug: $$(bootblock-objs) @printf " LINK $(subst $(obj)/,,$(@))\n" $(LD_bootblock) $(LDFLAGS_bootblock) -o $@ -L$(obj) \ @@ -82,6 +84,8 @@ romstage-y += \ $(top)/src/lib/memmove.c \ $(top)/src/lib/memset.c +romstage-$(CONFIG_RISCV_USE_ARCH_TIMER) += arch_timer.c + # Build the romstage $(objcbfs)/romstage.debug: $$(romstage-objs) @@ -118,6 +122,8 @@ ramstage-y += \ $(top)/src/lib/memmove.c \ $(top)/src/lib/memset.c +ramstage-$(CONFIG_RISCV_USE_ARCH_TIMER) += arch_timer.c + $(eval $(call create_class_compiler,rmodules,riscv)) ramstage-srcs += src/mainboard/$(MAINBOARDDIR)/mainboard.c diff --git a/src/arch/riscv/arch_timer.c b/src/arch/riscv/arch_timer.c new file mode 100644 index 0000000000..78157e6063 --- /dev/null +++ b/src/arch/riscv/arch_timer.c @@ -0,0 +1,28 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2018 Philipp Hug + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include + +void timer_monotonic_get(struct mono_time *mt) +{ + if (HLS()->time == NULL) + die("time not set in HLS"); + mono_time_set_usecs(mt, (long)read64((void *)(HLS()->time))); +} diff --git a/src/arch/riscv/include/arch/io.h b/src/arch/riscv/include/arch/io.h index 5f66a239b4..6fd0cac88e 100644 --- a/src/arch/riscv/include/arch/io.h +++ b/src/arch/riscv/include/arch/io.h @@ -33,6 +33,11 @@ static __always_inline uint32_t read32(const volatile void *addr) return *((volatile uint32_t *)(addr)); } +static __always_inline uint64_t read64(const volatile void *addr) +{ + return *((volatile uint64_t *)(addr)); +} + static __always_inline void write8(volatile void *addr, uint8_t value) { *((volatile uint8_t *)(addr)) = value; @@ -48,4 +53,9 @@ static __always_inline void write32(volatile void *addr, uint32_t value) *((volatile uint32_t *)(addr)) = value; } +static __always_inline void write64(volatile void *addr, uint64_t value) +{ + *((volatile uint64_t *)(addr)) = value; +} + #endif diff --git a/src/arch/riscv/misc.c b/src/arch/riscv/misc.c index 65b8ecf02f..1909dbc5f1 100644 --- a/src/arch/riscv/misc.c +++ b/src/arch/riscv/misc.c @@ -16,7 +16,3 @@ void init_timer(void) { } - -void udelay(unsigned int n) -{ -} diff --git a/src/soc/lowrisc/lowrisc/Kconfig b/src/soc/lowrisc/lowrisc/Kconfig index 71078b5c25..8b35231642 100644 --- a/src/soc/lowrisc/lowrisc/Kconfig +++ b/src/soc/lowrisc/lowrisc/Kconfig @@ -6,6 +6,9 @@ config SOC_LOWRISC_LOWRISC select ARCH_RAMSTAGE_RISCV select BOOTBLOCK_CONSOLE select DRIVERS_UART_8250MEM_32 + select GENERIC_UDELAY + select HAVE_MONOTONIC_TIMER + select RISCV_USE_ARCH_TIMER bool default n diff --git a/src/soc/sifive/fu540/Kconfig b/src/soc/sifive/fu540/Kconfig index 457d16bb4e..bee8292199 100644 --- a/src/soc/sifive/fu540/Kconfig +++ b/src/soc/sifive/fu540/Kconfig @@ -20,7 +20,11 @@ config SOC_SIFIVE_FU540 select ARCH_RAMSTAGE_RISCV select BOOTBLOCK_CONSOLE select DRIVERS_UART_SIFIVE + select GENERIC_UDELAY + select HAVE_MONOTONIC_TIMER + select RISCV_USE_ARCH_TIMER select UART_OVERRIDE_REFCLK + if SOC_SIFIVE_FU540 config RISCV_ARCH diff --git a/src/soc/ucb/riscv/Kconfig b/src/soc/ucb/riscv/Kconfig index 2a73f5c284..26adb56bfe 100644 --- a/src/soc/ucb/riscv/Kconfig +++ b/src/soc/ucb/riscv/Kconfig @@ -5,6 +5,9 @@ config SOC_UCB_RISCV select ARCH_ROMSTAGE_RISCV select ARCH_RAMSTAGE_RISCV select BOOTBLOCK_CONSOLE + select GENERIC_UDELAY + select HAVE_MONOTONIC_TIMER + select RISCV_USE_ARCH_TIMER bool default n