linux/arch/riscv/kernel/setup.c
Christoph Hellwig fcdc653751 riscv: provide native clint access for M-mode
RISC-V has the concept of a cpu level interrupt controller.  The
interface for it is split between a standardized part that is exposed
as bits in the mstatus/sstatus register and the mie/mip/sie/sip
CRS.  But the bit to actually trigger IPIs is not standardized and
just mentioned as implementable using MMIO.

Add support for IPIs using MMIO using the SiFive clint layout (which
is also shared by Ariane, Kendryte and the Qemu virt platform).
Additionally the MMIO block also supports the time value and timer
compare registers, so they are also set up using the same OF node.
Support for other layouts should also be relatively easy to add in the
future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: update include guard format; fix checkpatch
 issues; minor commit message cleanup]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-17 15:17:39 -08:00

87 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
* Chen Liqin <liqin.chen@sunplusct.com>
* Lennox Wu <lennox.wu@sunplusct.com>
* Copyright (C) 2012 Regents of the University of California
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/screen_info.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/sched/task.h>
#include <linux/swiotlb.h>
#include <asm/clint.h>
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
#include <asm/smp.h>
#include <asm/tlbflush.h>
#include <asm/thread_info.h>
#include "head.h"
#ifdef CONFIG_DUMMY_CONSOLE
struct screen_info screen_info = {
.orig_video_lines = 30,
.orig_video_cols = 80,
.orig_video_mode = 0,
.orig_video_ega_bx = 0,
.orig_video_isVGA = 1,
.orig_video_points = 8
};
#endif
/* The lucky hart to first increment this variable will boot the other cores */
atomic_t hart_lottery;
unsigned long boot_cpu_hartid;
void __init parse_dtb(void)
{
if (early_init_dt_scan(dtb_early_va))
return;
pr_err("No DTB passed to the kernel\n");
#ifdef CONFIG_CMDLINE_FORCE
strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
pr_info("Forcing kernel command line to: %s\n", boot_command_line);
#endif
}
void __init setup_arch(char **cmdline_p)
{
init_mm.start_code = (unsigned long) _stext;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = (unsigned long) _end;
*cmdline_p = boot_command_line;
parse_early_param();
setup_bootmem();
paging_init();
unflatten_device_tree();
clint_init_boot_cpu();
#ifdef CONFIG_SWIOTLB
swiotlb_init(1);
#endif
#ifdef CONFIG_SMP
setup_smp();
#endif
#ifdef CONFIG_DUMMY_CONSOLE
conswitchp = &dummy_con;
#endif
riscv_fill_hwcap();
}