linux-stable/arch/xtensa/kernel/setup.c
Max Filippov 89b184f980 xtensa: make secondary reset vector support conditional
Whether xtensa cores start from primary or secondary reset vector is
configurable and may be chosen by board designer or controlled at
runtime. When secondary reset vector is unused its location in memory
may not be writable.
Make secondary reset vector support conditional and don't build and load
secondary reset vector code when it is disabled.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-03-09 16:59:18 -08:00

704 lines
16 KiB
C

/*
* arch/xtensa/kernel/setup.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1995 Linus Torvalds
* Copyright (C) 2001 - 2005 Tensilica Inc.
* Copyright (C) 2014 - 2016 Cadence Design Systems Inc.
*
* Chris Zankel <chris@zankel.net>
* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
* Kevin Chea
* Marc Gauthier<marc@tensilica.com> <marc@alumni.uwaterloo.ca>
*/
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/screen_info.h>
#include <linux/kernel.h>
#include <linux/percpu.h>
#include <linux/cpu.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
# include <linux/console.h>
#endif
#ifdef CONFIG_PROC_FS
# include <linux/seq_file.h>
#endif
#include <asm/bootparam.h>
#include <asm/kasan.h>
#include <asm/mmu_context.h>
#include <asm/page.h>
#include <asm/param.h>
#include <asm/platform.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp.h>
#include <asm/sysmem.h>
#include <asm/timex.h>
#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
struct screen_info screen_info = {
.orig_x = 0,
.orig_y = 24,
.orig_video_cols = 80,
.orig_video_lines = 24,
.orig_video_isVGA = 1,
.orig_video_points = 16,
};
#endif
#ifdef CONFIG_BLK_DEV_INITRD
extern unsigned long initrd_start;
extern unsigned long initrd_end;
extern int initrd_below_start_ok;
#endif
#ifdef CONFIG_USE_OF
void *dtb_start = __dtb_start;
#endif
extern unsigned long loops_per_jiffy;
/* Command line specified as configuration option. */
static char __initdata command_line[COMMAND_LINE_SIZE];
#ifdef CONFIG_CMDLINE_BOOL
static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
#endif
#ifdef CONFIG_PARSE_BOOTPARAM
/*
* Boot parameter parsing.
*
* The Xtensa port uses a list of variable-sized tags to pass data to
* the kernel. The first tag must be a BP_TAG_FIRST tag for the list
* to be recognised. The list is terminated with a zero-sized
* BP_TAG_LAST tag.
*/
typedef struct tagtable {
u32 tag;
int (*parse)(const bp_tag_t*);
} tagtable_t;
#define __tagtable(tag, fn) static tagtable_t __tagtable_##fn \
__section(".taglist") __attribute__((used)) = { tag, fn }
/* parse current tag */
static int __init parse_tag_mem(const bp_tag_t *tag)
{
struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
if (mi->type != MEMORY_TYPE_CONVENTIONAL)
return -1;
return memblock_add(mi->start, mi->end - mi->start);
}
__tagtable(BP_TAG_MEMORY, parse_tag_mem);
#ifdef CONFIG_BLK_DEV_INITRD
static int __init parse_tag_initrd(const bp_tag_t* tag)
{
struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
initrd_start = (unsigned long)__va(mi->start);
initrd_end = (unsigned long)__va(mi->end);
return 0;
}
__tagtable(BP_TAG_INITRD, parse_tag_initrd);
#endif /* CONFIG_BLK_DEV_INITRD */
#ifdef CONFIG_USE_OF
static int __init parse_tag_fdt(const bp_tag_t *tag)
{
dtb_start = __va(tag->data[0]);
return 0;
}
__tagtable(BP_TAG_FDT, parse_tag_fdt);
#endif /* CONFIG_USE_OF */
static int __init parse_tag_cmdline(const bp_tag_t* tag)
{
strscpy(command_line, (char *)(tag->data), COMMAND_LINE_SIZE);
return 0;
}
__tagtable(BP_TAG_COMMAND_LINE, parse_tag_cmdline);
static int __init parse_bootparam(const bp_tag_t* tag)
{
extern tagtable_t __tagtable_begin, __tagtable_end;
tagtable_t *t;
/* Boot parameters must start with a BP_TAG_FIRST tag. */
if (tag->id != BP_TAG_FIRST) {
pr_warn("Invalid boot parameters!\n");
return 0;
}
tag = (bp_tag_t*)((unsigned long)tag + sizeof(bp_tag_t) + tag->size);
/* Parse all tags. */
while (tag != NULL && tag->id != BP_TAG_LAST) {
for (t = &__tagtable_begin; t < &__tagtable_end; t++) {
if (tag->id == t->tag) {
t->parse(tag);
break;
}
}
if (t == &__tagtable_end)
pr_warn("Ignoring tag 0x%08x\n", tag->id);
tag = (bp_tag_t*)((unsigned long)(tag + 1) + tag->size);
}
return 0;
}
#else
static int __init parse_bootparam(const bp_tag_t *tag)
{
pr_info("Ignoring boot parameters at %p\n", tag);
return 0;
}
#endif
#ifdef CONFIG_USE_OF
#if !XCHAL_HAVE_PTP_MMU || XCHAL_HAVE_SPANNING_WAY
unsigned long xtensa_kio_paddr = XCHAL_KIO_DEFAULT_PADDR;
EXPORT_SYMBOL(xtensa_kio_paddr);
static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
int depth, void *data)
{
const __be32 *ranges;
int len;
if (depth > 1)
return 0;
if (!of_flat_dt_is_compatible(node, "simple-bus"))
return 0;
ranges = of_get_flat_dt_prop(node, "ranges", &len);
if (!ranges)
return 1;
if (len == 0)
return 1;
xtensa_kio_paddr = of_read_ulong(ranges+1, 1);
/* round down to nearest 256MB boundary */
xtensa_kio_paddr &= 0xf0000000;
init_kio();
return 1;
}
#else
static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
int depth, void *data)
{
return 1;
}
#endif
void __init early_init_devtree(void *params)
{
early_init_dt_scan(params);
of_scan_flat_dt(xtensa_dt_io_area, NULL);
if (!command_line[0])
strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
}
#endif /* CONFIG_USE_OF */
/*
* Initialize architecture. (Early stage)
*/
void __init init_arch(bp_tag_t *bp_start)
{
/* Initialize MMU. */
init_mmu();
/* Initialize initial KASAN shadow map */
kasan_early_init();
/* Parse boot parameters */
if (bp_start)
parse_bootparam(bp_start);
#ifdef CONFIG_USE_OF
early_init_devtree(dtb_start);
#endif
#ifdef CONFIG_CMDLINE_BOOL
if (!command_line[0])
strscpy(command_line, default_command_line, COMMAND_LINE_SIZE);
#endif
/* Early hook for platforms */
platform_init(bp_start);
}
/*
* Initialize system. Setup memory and reserve regions.
*/
static inline int __init_memblock mem_reserve(unsigned long start,
unsigned long end)
{
return memblock_reserve(start, end - start);
}
void __init setup_arch(char **cmdline_p)
{
pr_info("config ID: %08x:%08x\n",
xtensa_get_sr(SREG_EPC), xtensa_get_sr(SREG_EXCSAVE));
if (xtensa_get_sr(SREG_EPC) != XCHAL_HW_CONFIGID0 ||
xtensa_get_sr(SREG_EXCSAVE) != XCHAL_HW_CONFIGID1)
pr_info("built for config ID: %08x:%08x\n",
XCHAL_HW_CONFIGID0, XCHAL_HW_CONFIGID1);
*cmdline_p = command_line;
platform_setup(cmdline_p);
strscpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
/* Reserve some memory regions */
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start < initrd_end &&
!mem_reserve(__pa(initrd_start), __pa(initrd_end)))
initrd_below_start_ok = 1;
else
initrd_start = 0;
#endif
mem_reserve(__pa(_stext), __pa(_end));
#ifdef CONFIG_XIP_KERNEL
mem_reserve(__pa(_xip_start), __pa(_xip_end));
#endif
#ifdef CONFIG_VECTORS_ADDR
#ifdef SUPPORT_WINDOWED
mem_reserve(__pa(_WindowVectors_text_start),
__pa(_WindowVectors_text_end));
#endif
mem_reserve(__pa(_DebugInterruptVector_text_start),
__pa(_DebugInterruptVector_text_end));
mem_reserve(__pa(_KernelExceptionVector_text_start),
__pa(_KernelExceptionVector_text_end));
mem_reserve(__pa(_UserExceptionVector_text_start),
__pa(_UserExceptionVector_text_end));
mem_reserve(__pa(_DoubleExceptionVector_text_start),
__pa(_DoubleExceptionVector_text_end));
mem_reserve(__pa(_exception_text_start),
__pa(_exception_text_end));
#if XCHAL_EXCM_LEVEL >= 2
mem_reserve(__pa(_Level2InterruptVector_text_start),
__pa(_Level2InterruptVector_text_end));
#endif
#if XCHAL_EXCM_LEVEL >= 3
mem_reserve(__pa(_Level3InterruptVector_text_start),
__pa(_Level3InterruptVector_text_end));
#endif
#if XCHAL_EXCM_LEVEL >= 4
mem_reserve(__pa(_Level4InterruptVector_text_start),
__pa(_Level4InterruptVector_text_end));
#endif
#if XCHAL_EXCM_LEVEL >= 5
mem_reserve(__pa(_Level5InterruptVector_text_start),
__pa(_Level5InterruptVector_text_end));
#endif
#if XCHAL_EXCM_LEVEL >= 6
mem_reserve(__pa(_Level6InterruptVector_text_start),
__pa(_Level6InterruptVector_text_end));
#endif
#endif /* CONFIG_VECTORS_ADDR */
#ifdef CONFIG_SECONDARY_RESET_VECTOR
mem_reserve(__pa(_SecondaryResetVector_text_start),
__pa(_SecondaryResetVector_text_end));
#endif
parse_early_param();
bootmem_init();
kasan_init();
unflatten_and_copy_device_tree();
#ifdef CONFIG_SMP
smp_init_cpus();
#endif
paging_init();
zones_init();
#ifdef CONFIG_VT
# if defined(CONFIG_VGA_CONSOLE)
conswitchp = &vga_con;
# endif
#endif
}
static DEFINE_PER_CPU(struct cpu, cpu_data);
static int __init topology_init(void)
{
int i;
for_each_possible_cpu(i) {
struct cpu *cpu = &per_cpu(cpu_data, i);
cpu->hotpluggable = !!i;
register_cpu(cpu, i);
}
return 0;
}
subsys_initcall(topology_init);
void cpu_reset(void)
{
#if XCHAL_HAVE_PTP_MMU && IS_ENABLED(CONFIG_MMU)
local_irq_disable();
/*
* We have full MMU: all autoload ways, ways 7, 8 and 9 of DTLB must
* be flushed.
* Way 4 is not currently used by linux.
* Ways 5 and 6 shall not be touched on MMUv2 as they are hardwired.
* Way 5 shall be flushed and way 6 shall be set to identity mapping
* on MMUv3.
*/
local_flush_tlb_all();
invalidate_page_directory();
#if XCHAL_HAVE_SPANNING_WAY
/* MMU v3 */
{
unsigned long vaddr = (unsigned long)cpu_reset;
unsigned long paddr = __pa(vaddr);
unsigned long tmpaddr = vaddr + SZ_512M;
unsigned long tmp0, tmp1, tmp2, tmp3;
/*
* Find a place for the temporary mapping. It must not be
* in the same 512MB region with vaddr or paddr, otherwise
* there may be multihit exception either on entry to the
* temporary mapping, or on entry to the identity mapping.
* (512MB is the biggest page size supported by TLB.)
*/
while (((tmpaddr ^ paddr) & -SZ_512M) == 0)
tmpaddr += SZ_512M;
/* Invalidate mapping in the selected temporary area */
if (itlb_probe(tmpaddr) & BIT(ITLB_HIT_BIT))
invalidate_itlb_entry(itlb_probe(tmpaddr));
if (itlb_probe(tmpaddr + PAGE_SIZE) & BIT(ITLB_HIT_BIT))
invalidate_itlb_entry(itlb_probe(tmpaddr + PAGE_SIZE));
/*
* Map two consecutive pages starting at the physical address
* of this function to the temporary mapping area.
*/
write_itlb_entry(__pte((paddr & PAGE_MASK) |
_PAGE_HW_VALID |
_PAGE_HW_EXEC |
_PAGE_CA_BYPASS),
tmpaddr & PAGE_MASK);
write_itlb_entry(__pte(((paddr & PAGE_MASK) + PAGE_SIZE) |
_PAGE_HW_VALID |
_PAGE_HW_EXEC |
_PAGE_CA_BYPASS),
(tmpaddr & PAGE_MASK) + PAGE_SIZE);
/* Reinitialize TLB */
__asm__ __volatile__ ("movi %0, 1f\n\t"
"movi %3, 2f\n\t"
"add %0, %0, %4\n\t"
"add %3, %3, %5\n\t"
"jx %0\n"
/*
* No literal, data or stack access
* below this point
*/
"1:\n\t"
/* Initialize *tlbcfg */
"movi %0, 0\n\t"
"wsr %0, itlbcfg\n\t"
"wsr %0, dtlbcfg\n\t"
/* Invalidate TLB way 5 */
"movi %0, 4\n\t"
"movi %1, 5\n"
"1:\n\t"
"iitlb %1\n\t"
"idtlb %1\n\t"
"add %1, %1, %6\n\t"
"addi %0, %0, -1\n\t"
"bnez %0, 1b\n\t"
/* Initialize TLB way 6 */
"movi %0, 7\n\t"
"addi %1, %9, 3\n\t"
"addi %2, %9, 6\n"
"1:\n\t"
"witlb %1, %2\n\t"
"wdtlb %1, %2\n\t"
"add %1, %1, %7\n\t"
"add %2, %2, %7\n\t"
"addi %0, %0, -1\n\t"
"bnez %0, 1b\n\t"
"isync\n\t"
/* Jump to identity mapping */
"jx %3\n"
"2:\n\t"
/* Complete way 6 initialization */
"witlb %1, %2\n\t"
"wdtlb %1, %2\n\t"
/* Invalidate temporary mapping */
"sub %0, %9, %7\n\t"
"iitlb %0\n\t"
"add %0, %0, %8\n\t"
"iitlb %0"
: "=&a"(tmp0), "=&a"(tmp1), "=&a"(tmp2),
"=&a"(tmp3)
: "a"(tmpaddr - vaddr),
"a"(paddr - vaddr),
"a"(SZ_128M), "a"(SZ_512M),
"a"(PAGE_SIZE),
"a"((tmpaddr + SZ_512M) & PAGE_MASK)
: "memory");
}
#endif
#endif
__asm__ __volatile__ ("movi a2, 0\n\t"
"wsr a2, icountlevel\n\t"
"movi a2, 0\n\t"
"wsr a2, icount\n\t"
#if XCHAL_NUM_IBREAK > 0
"wsr a2, ibreakenable\n\t"
#endif
#if XCHAL_HAVE_LOOPS
"wsr a2, lcount\n\t"
#endif
"movi a2, 0x1f\n\t"
"wsr a2, ps\n\t"
"isync\n\t"
"jx %0\n\t"
:
: "a" (XCHAL_RESET_VECTOR_VADDR)
: "a2");
for (;;)
;
}
void machine_restart(char * cmd)
{
platform_restart();
}
void machine_halt(void)
{
platform_halt();
while (1);
}
void machine_power_off(void)
{
platform_power_off();
while (1);
}
#ifdef CONFIG_PROC_FS
/*
* Display some core information through /proc/cpuinfo.
*/
static int
c_show(struct seq_file *f, void *slot)
{
/* high-level stuff */
seq_printf(f, "CPU count\t: %u\n"
"CPU list\t: %*pbl\n"
"vendor_id\t: Tensilica\n"
"model\t\t: Xtensa " XCHAL_HW_VERSION_NAME "\n"
"core ID\t\t: " XCHAL_CORE_ID "\n"
"build ID\t: 0x%x\n"
"config ID\t: %08x:%08x\n"
"byte order\t: %s\n"
"cpu MHz\t\t: %lu.%02lu\n"
"bogomips\t: %lu.%02lu\n",
num_online_cpus(),
cpumask_pr_args(cpu_online_mask),
XCHAL_BUILD_UNIQUE_ID,
xtensa_get_sr(SREG_EPC), xtensa_get_sr(SREG_EXCSAVE),
XCHAL_HAVE_BE ? "big" : "little",
ccount_freq/1000000,
(ccount_freq/10000) % 100,
loops_per_jiffy/(500000/HZ),
(loops_per_jiffy/(5000/HZ)) % 100);
seq_puts(f, "flags\t\t: "
#if XCHAL_HAVE_NMI
"nmi "
#endif
#if XCHAL_HAVE_DEBUG
"debug "
# if XCHAL_HAVE_OCD
"ocd "
# endif
#endif
#if XCHAL_HAVE_DENSITY
"density "
#endif
#if XCHAL_HAVE_BOOLEANS
"boolean "
#endif
#if XCHAL_HAVE_LOOPS
"loop "
#endif
#if XCHAL_HAVE_NSA
"nsa "
#endif
#if XCHAL_HAVE_MINMAX
"minmax "
#endif
#if XCHAL_HAVE_SEXT
"sext "
#endif
#if XCHAL_HAVE_CLAMPS
"clamps "
#endif
#if XCHAL_HAVE_MAC16
"mac16 "
#endif
#if XCHAL_HAVE_MUL16
"mul16 "
#endif
#if XCHAL_HAVE_MUL32
"mul32 "
#endif
#if XCHAL_HAVE_MUL32_HIGH
"mul32h "
#endif
#if XCHAL_HAVE_FP
"fpu "
#endif
#if XCHAL_HAVE_S32C1I
"s32c1i "
#endif
#if XCHAL_HAVE_EXCLUSIVE
"exclusive "
#endif
"\n");
/* Registers. */
seq_printf(f,"physical aregs\t: %d\n"
"misc regs\t: %d\n"
"ibreak\t\t: %d\n"
"dbreak\t\t: %d\n",
XCHAL_NUM_AREGS,
XCHAL_NUM_MISC_REGS,
XCHAL_NUM_IBREAK,
XCHAL_NUM_DBREAK);
/* Interrupt. */
seq_printf(f,"num ints\t: %d\n"
"ext ints\t: %d\n"
"int levels\t: %d\n"
"timers\t\t: %d\n"
"debug level\t: %d\n",
XCHAL_NUM_INTERRUPTS,
XCHAL_NUM_EXTINTERRUPTS,
XCHAL_NUM_INTLEVELS,
XCHAL_NUM_TIMERS,
XCHAL_DEBUGLEVEL);
/* Cache */
seq_printf(f,"icache line size: %d\n"
"icache ways\t: %d\n"
"icache size\t: %d\n"
"icache flags\t: "
#if XCHAL_ICACHE_LINE_LOCKABLE
"lock "
#endif
"\n"
"dcache line size: %d\n"
"dcache ways\t: %d\n"
"dcache size\t: %d\n"
"dcache flags\t: "
#if XCHAL_DCACHE_IS_WRITEBACK
"writeback "
#endif
#if XCHAL_DCACHE_LINE_LOCKABLE
"lock "
#endif
"\n",
XCHAL_ICACHE_LINESIZE,
XCHAL_ICACHE_WAYS,
XCHAL_ICACHE_SIZE,
XCHAL_DCACHE_LINESIZE,
XCHAL_DCACHE_WAYS,
XCHAL_DCACHE_SIZE);
return 0;
}
/*
* We show only CPU #0 info.
*/
static void *
c_start(struct seq_file *f, loff_t *pos)
{
return (*pos == 0) ? (void *)1 : NULL;
}
static void *
c_next(struct seq_file *f, void *v, loff_t *pos)
{
++*pos;
return c_start(f, pos);
}
static void
c_stop(struct seq_file *f, void *v)
{
}
const struct seq_operations cpuinfo_op =
{
.start = c_start,
.next = c_next,
.stop = c_stop,
.show = c_show,
};
#endif /* CONFIG_PROC_FS */