[U-Boot] [PATCH v2 1/7] riscv: Add a SYSCON driver for Andestech's PLIC

Rick Chen
2019-04-01T05:47:08Z

Hi Bin

Bin Meng <bmeng.cn@gmail.com> 於 2019年3月29日 週五 下午5:20寫道：
>
> Hi Rick,
>
> On Mon, Mar 25, 2019 at 3:39 PM Andes <uboot@andestech.com> wrote:
> >
> > From: Rick Chen <rick@andestech.com>
> >
> > The Platform-Level Interrupt Controller(PLIC)
>
> nits: it should have a space before (PLIC)

OK

>
> > 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>
> > ---
> > arch/riscv/Kconfig | 9 +++
> > arch/riscv/include/asm/global_data.h | 3 +
> > arch/riscv/include/asm/syscon.h | 2 +-
> > arch/riscv/lib/Makefile | 1 +
> > arch/riscv/lib/andes_plic.c | 111 +++++++++++++++++++++++++++++++++++
> > 5 files changed, 125 insertions(+), 1 deletion(-)
> > create mode 100644 arch/riscv/lib/andes_plic.c
> >
>
> Could you please include a changelog in the future?

OK

>
> > 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..c1b4b86 100644
> > --- a/arch/riscv/include/asm/syscon.h
> > +++ b/arch/riscv/include/asm/syscon.h
> > @@ -9,11 +9,11 @@
> > /*
> > * 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..abf8a73
> > --- /dev/null
> > +++ b/arch/riscv/lib/andes_plic.c
> > @@ -0,0 +1,111 @@
> > +// 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;
> > +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)
> > +
> > +int plic_init(int harts)
>
> nits: suggest change the name to enable_ipi(), to better refelct what
> is done in the function, and it should be "static"

OK

>
> > +{
> > + int i;
> > + int en = ENABLE_HART_IPI;
> > +
> > + PLIC_BASE_GET();
>
> There is no need to call PLIC_BASE_GET() here.

OK

>
> > + for (i = 0; i < harts ;i++)
> > + {
> > + en = en >> i;
> > + writel(en, (void __iomem *)ENABLE_REG(gd->arch.plic, i));
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +int init_plic(void)
>
> nits: it should be "static"

OK

>
> > +{
> > + struct udevice *dev;
> > + int ret;
> > +
> > + ret = uclass_find_first_device(UCLASS_CPU, &dev);
> > + if (ret)
> > + return ret;
> > +
> > + if (ret == 0 && dev != NULL) {
> > + ret = cpu_get_count(dev);
> > + plic_init(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(nds_plic) = {
> > + .name = "andes_plic",
> > + .id = UCLASS_SYSCON,
> > + .of_match = andes_plic_ids,
> > + .flags = DM_FLAG_PRE_RELOC,
> > +};
> > --
>
> Regards,
> Bin

Thanks for review.
Rick