From: Rick Chen rick@andestech.com
The Platform-Level Interrupt Controller (PLIC) block holds memory-mapped claim and pending registers associated with software interrupt. It is required for handling IPI.
Signed-off-by: Rick Chen rick@andestech.com Cc: Greentime Hu greentime@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- Changes in V4: - Drop the empty comment line - Check return value after cpu_get_count() - Rename nds_plic as andes_plic - Fix checkpatch error issues
arch/riscv/Kconfig | 9 +++ arch/riscv/include/asm/global_data.h | 3 + arch/riscv/include/asm/syscon.h | 3 +- arch/riscv/lib/Makefile | 1 + arch/riscv/lib/andes_plic.c | 113 +++++++++++++++++++++++++++++++++++ 5 files changed, 127 insertions(+), 2 deletions(-) create mode 100644 arch/riscv/lib/andes_plic.c
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 3a4470d..511768b 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -109,6 +109,15 @@ config SIFIVE_CLINT The SiFive CLINT block holds memory-mapped control and status registers associated with software and timer interrupts.
+config ANDES_PLIC + bool + depends on RISCV_MMODE + select REGMAP + select SYSCON + help + The Andes PLIC block holds memory-mapped claim and pending registers + associated with software interrupt. + 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 80e3165..b867910 100644 --- a/arch/riscv/include/asm/global_data.h +++ b/arch/riscv/include/asm/global_data.h @@ -18,6 +18,9 @@ struct arch_global_data { #ifdef CONFIG_SIFIVE_CLINT void __iomem *clint; /* clint base address */ #endif +#ifdef CONFIG_ANDES_PLIC + void __iomem *plic; /* plic 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 d311ee6..a086208 100644 --- a/arch/riscv/include/asm/syscon.h +++ b/arch/riscv/include/asm/syscon.h @@ -8,12 +8,11 @@
/* * System controllers in a RISC-V system - * - * So far only SiFive's Core Local Interruptor (CLINT) is defined. */ enum { RISCV_NONE, RISCV_SYSCON_CLINT, /* Core Local Interruptor (CLINT) */ + RISCV_SYSCON_PLIC, /* Platform Level Interrupt Controller (PLIC) */ };
#endif /* _ASM_SYSCON_H */ diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index 35dbf64..1bf554b 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_CMD_GO) += boot.o obj-y += cache.o obj-$(CONFIG_RISCV_RDTIME) += rdtime.o obj-$(CONFIG_SIFIVE_CLINT) += sifive_clint.o +obj-$(CONFIG_ANDES_PLIC) += andes_plic.o obj-y += interrupts.o obj-y += reset.o obj-$(CONFIG_SBI_IPI) += sbi_ipi.o diff --git a/arch/riscv/lib/andes_plic.c b/arch/riscv/lib/andes_plic.c new file mode 100644 index 0000000..2ffe49a --- /dev/null +++ b/arch/riscv/lib/andes_plic.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2019, Rick Chen rick@andestech.com + * + * U-Boot syscon driver for Andes's Platform Level Interrupt Controller (PLIC). + * The PLIC block holds memory-mapped claim and pending registers + * associated with software interrupt. + */ + +#include <common.h> +#include <dm.h> +#include <dm/device-internal.h> +#include <dm/lists.h> +#include <dm/uclass-internal.h> +#include <regmap.h> +#include <syscon.h> +#include <asm/io.h> +#include <asm/syscon.h> +#include <cpu.h> + +/* pending register */ +#define PENDING_REG(base, hart) ((ulong)(base) + 0x1000 + (hart) * 8) +/* enable register */ +#define ENABLE_REG(base, hart) ((ulong)(base) + 0x2000 + (hart) * 0x80) +/* claim register */ +#define CLAIM_REG(base, hart) ((ulong)(base) + 0x200004 + (hart) * 0x1000) + +#define ENABLE_HART_IPI (0x80808080) +#define SEND_IPI_TO_HART(hart) (0x80 >> (hart)) + +DECLARE_GLOBAL_DATA_PTR; +static int init_plic(void); + +#define PLIC_BASE_GET(void) \ + do { \ + long *ret; \ + \ + if (!gd->arch.plic) { \ + ret = syscon_get_first_range(RISCV_SYSCON_PLIC); \ + if (IS_ERR(ret)) \ + return PTR_ERR(ret); \ + gd->arch.plic = ret; \ + init_plic(); \ + } \ + } while (0) + +static int enable_ipi(int harts) +{ + int i; + int en = ENABLE_HART_IPI; + + for (i = 0; i < harts; i++) { + en = en >> i; + writel(en, (void __iomem *)ENABLE_REG(gd->arch.plic, i)); + } + + return 0; +} + +static int init_plic(void) +{ + struct udevice *dev; + int ret; + + ret = uclass_find_first_device(UCLASS_CPU, &dev); + if (ret) + return ret; + + if (ret == 0 && dev) { + ret = cpu_get_count(dev); + if (ret < 0) + return ret; + + enable_ipi(ret); + return 0; + } + + return -ENODEV; +} + +int riscv_send_ipi(int hart) +{ + PLIC_BASE_GET(); + + writel(SEND_IPI_TO_HART(hart), + (void __iomem *)PENDING_REG(gd->arch.plic, gd->arch.boot_hart)); + + return 0; +} + +int riscv_clear_ipi(int hart) +{ + u32 source_id; + + PLIC_BASE_GET(); + + source_id = readl((void __iomem *)CLAIM_REG(gd->arch.plic, hart)); + writel(source_id, (void __iomem *)CLAIM_REG(gd->arch.plic, hart)); + + return 0; +} + +static const struct udevice_id andes_plic_ids[] = { + { .compatible = "riscv,plic1", .data = RISCV_SYSCON_PLIC }, + { } +}; + +U_BOOT_DRIVER(andes_plic) = { + .name = "andes_plic", + .id = UCLASS_SYSCON, + .of_match = andes_plic_ids, + .flags = DM_FLAG_PRE_RELOC, +};