zephyr/arch/xtensa/core/xtensa-asm2.c

305 lines
8.3 KiB
C

/*
* Copyright (c) 2017, Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <string.h>
#include <xtensa-asm2.h>
#include <zephyr/kernel.h>
#include <ksched.h>
#include <zephyr/kernel_structs.h>
#include <kernel_internal.h>
#include <kswap.h>
#include <_soc_inthandlers.h>
#include <zephyr/toolchain.h>
#include <zephyr/logging/log.h>
LOG_MODULE_DECLARE(os, CONFIG_KERNEL_LOG_LEVEL);
extern char xtensa_arch_except_epc[];
void *xtensa_init_stack(struct k_thread *thread, int *stack_top,
void (*entry)(void *, void *, void *),
void *arg1, void *arg2, void *arg3)
{
/* Not-a-cpu ID Ensures that the first time this is run, the
* stack will be invalidated. That covers the edge case of
* restarting a thread on a stack that had previously been run
* on one CPU, but then initialized on this one, and
* potentially run THERE and not HERE.
*/
thread->arch.last_cpu = -1;
/* We cheat and shave 16 bytes off, the top four words are the
* A0-A3 spill area for the caller of the entry function,
* which doesn't exist. It will never be touched, so we
* arrange to enter the function with a CALLINC of 1 and a
* stack pointer 16 bytes above the top, so its ENTRY at the
* start will decrement the stack pointer by 16.
*/
const int bsasz = BASE_SAVE_AREA_SIZE - 16;
void *ret, **bsa = (void **) (((char *) stack_top) - bsasz);
(void)memset(bsa, 0, bsasz);
bsa[BSA_PC_OFF/4] = z_thread_entry;
bsa[BSA_PS_OFF/4] = (void *)(PS_WOE | PS_UM | PS_CALLINC(1));
#if XCHAL_HAVE_THREADPTR && defined(CONFIG_THREAD_LOCAL_STORAGE)
bsa[BSA_THREADPTR_OFF/4] = UINT_TO_POINTER(thread->tls);
#endif
/* Arguments to z_thread_entry(). Remember these start at A6,
* which will be rotated into A2 by the ENTRY instruction that
* begins the C function. And A4-A7 and A8-A11 are optional
* quads that live below the BSA!
*/
bsa[-1] = arg1; /* a7 */
bsa[-2] = entry; /* a6 */
bsa[-3] = 0; /* a5 */
bsa[-4] = 0; /* a4 */
bsa[-5] = 0; /* a11 */
bsa[-6] = 0; /* a10 */
bsa[-7] = arg3; /* a9 */
bsa[-8] = arg2; /* a8 */
/* Finally push the BSA pointer and return the stack pointer
* as the handle
*/
bsa[-9] = bsa;
ret = &bsa[-9];
return ret;
}
void arch_new_thread(struct k_thread *thread, k_thread_stack_t *stack,
char *stack_ptr, k_thread_entry_t entry,
void *p1, void *p2, void *p3)
{
thread->switch_handle = xtensa_init_stack(thread,
(int *)stack_ptr, entry,
p1, p2, p3);
#ifdef CONFIG_KERNEL_COHERENCE
__ASSERT((((size_t)stack) % XCHAL_DCACHE_LINESIZE) == 0, "");
__ASSERT((((size_t)stack_ptr) % XCHAL_DCACHE_LINESIZE) == 0, "");
z_xtensa_cache_flush_inv(stack, (char *)stack_ptr - (char *)stack);
#endif
}
void z_irq_spurious(const void *arg)
{
int irqs, ie;
ARG_UNUSED(arg);
__asm__ volatile("rsr.interrupt %0" : "=r"(irqs));
__asm__ volatile("rsr.intenable %0" : "=r"(ie));
LOG_ERR(" ** Spurious INTERRUPT(s) %p, INTENABLE = %p",
(void *)irqs, (void *)ie);
z_xtensa_fatal_error(K_ERR_SPURIOUS_IRQ, NULL);
}
void z_xtensa_dump_stack(const z_arch_esf_t *stack)
{
int *bsa = *(int **)stack;
LOG_ERR(" ** A0 %p SP %p A2 %p A3 %p",
(void *)bsa[BSA_A0_OFF/4],
((char *)bsa) + BASE_SAVE_AREA_SIZE,
(void *)bsa[BSA_A2_OFF/4], (void *)bsa[BSA_A3_OFF/4]);
if (bsa - stack > 4) {
LOG_ERR(" ** A4 %p A5 %p A6 %p A7 %p",
(void *)bsa[-4], (void *)bsa[-3],
(void *)bsa[-2], (void *)bsa[-1]);
}
if (bsa - stack > 8) {
LOG_ERR(" ** A8 %p A9 %p A10 %p A11 %p",
(void *)bsa[-8], (void *)bsa[-7],
(void *)bsa[-6], (void *)bsa[-5]);
}
if (bsa - stack > 12) {
LOG_ERR(" ** A12 %p A13 %p A14 %p A15 %p",
(void *)bsa[-12], (void *)bsa[-11],
(void *)bsa[-10], (void *)bsa[-9]);
}
#if XCHAL_HAVE_LOOPS
LOG_ERR(" ** LBEG %p LEND %p LCOUNT %p",
(void *)bsa[BSA_LBEG_OFF/4],
(void *)bsa[BSA_LEND_OFF/4],
(void *)bsa[BSA_LCOUNT_OFF/4]);
#endif
LOG_ERR(" ** SAR %p", (void *)bsa[BSA_SAR_OFF/4]);
}
static inline unsigned int get_bits(int offset, int num_bits, unsigned int val)
{
int mask;
mask = BIT(num_bits) - 1;
val = val >> offset;
return val & mask;
}
static ALWAYS_INLINE void usage_stop(void)
{
#ifdef CONFIG_SCHED_THREAD_USAGE
z_sched_usage_stop();
#endif
}
static inline void *return_to(void *interrupted)
{
return _current_cpu->nested <= 1 ?
z_get_next_switch_handle(interrupted) : interrupted;
}
/* The wrapper code lives here instead of in the python script that
* generates _xtensa_handle_one_int*(). Seems cleaner, still kind of
* ugly.
*
* This may be unused depending on number of interrupt levels
* supported by the SoC.
*/
#define DEF_INT_C_HANDLER(l) \
__unused void *xtensa_int##l##_c(void *interrupted_stack) \
{ \
uint32_t irqs, intenable, m; \
usage_stop(); \
__asm__ volatile("rsr.interrupt %0" : "=r"(irqs)); \
__asm__ volatile("rsr.intenable %0" : "=r"(intenable)); \
irqs &= intenable; \
while ((m = _xtensa_handle_one_int##l(irqs))) { \
irqs ^= m; \
__asm__ volatile("wsr.intclear %0" : : "r"(m)); \
} \
return return_to(interrupted_stack); \
}
#if XCHAL_NMILEVEL >= 2
DEF_INT_C_HANDLER(2)
#endif
#if XCHAL_NMILEVEL >= 3
DEF_INT_C_HANDLER(3)
#endif
#if XCHAL_NMILEVEL >= 4
DEF_INT_C_HANDLER(4)
#endif
#if XCHAL_NMILEVEL >= 5
DEF_INT_C_HANDLER(5)
#endif
#if XCHAL_NMILEVEL >= 6
DEF_INT_C_HANDLER(6)
#endif
#if XCHAL_NMILEVEL >= 7
DEF_INT_C_HANDLER(7)
#endif
static inline DEF_INT_C_HANDLER(1)
/* C handler for level 1 exceptions/interrupts. Hooked from the
* DEF_EXCINT 1 vector declaration in assembly code. This one looks
* different because exceptions and interrupts land at the same
* vector; other interrupt levels have their own vectors.
*/
void *xtensa_excint1_c(int *interrupted_stack)
{
int cause, vaddr, *bsa = *(int **)interrupted_stack;
__asm__ volatile("rsr.exccause %0" : "=r"(cause));
if (cause == EXCCAUSE_LEVEL1_INTERRUPT) {
return xtensa_int1_c(interrupted_stack);
} else if (cause == EXCCAUSE_SYSCALL) {
/* Just report it to the console for now */
LOG_ERR(" ** SYSCALL PS %p PC %p",
(void *)bsa[BSA_PS_OFF/4], (void *)bsa[BSA_PC_OFF/4]);
z_xtensa_dump_stack(interrupted_stack);
/* Xtensa exceptions don't automatically advance PC,
* have to skip the SYSCALL instruction manually or
* else it will just loop forever
*/
bsa[BSA_PC_OFF/4] += 3;
} else {
uint32_t ps = bsa[BSA_PS_OFF/4];
void *pc = (void *)bsa[BSA_PC_OFF/4];
__asm__ volatile("rsr.excvaddr %0" : "=r"(vaddr));
/* Default for exception */
int reason = K_ERR_CPU_EXCEPTION;
/* We need to distinguish between an ill in xtensa_arch_except,
* e.g for k_panic, and any other ill. For exceptions caused by
* xtensa_arch_except calls, we also need to pass the reason_p
* to z_xtensa_fatal_error. Since the ARCH_EXCEPT frame is in the
* BSA, the first arg reason_p is stored at the A2 offset.
* We assign EXCCAUSE the unused, reserved code 63; this may be
* problematic if the app or new boards also decide to repurpose
* this code.
*/
if ((pc == (void *) &xtensa_arch_except_epc) && (cause == 0)) {
cause = 63;
__asm__ volatile("wsr.exccause %0" : : "r"(cause));
reason = bsa[BSA_A2_OFF/4];
/* Skip ILL to RETW */
bsa[BSA_PC_OFF/4] += 3;
pc = (void *)bsa[BSA_PC_OFF/4];
}
LOG_ERR(" ** FATAL EXCEPTION");
LOG_ERR(" ** CPU %d EXCCAUSE %d (%s)",
arch_curr_cpu()->id, cause,
z_xtensa_exccause(cause));
LOG_ERR(" ** PC %p VADDR %p",
pc, (void *)vaddr);
LOG_ERR(" ** PS %p", (void *)bsa[BSA_PS_OFF/4]);
LOG_ERR(" ** (INTLEVEL:%d EXCM: %d UM:%d RING:%d WOE:%d OWB:%d CALLINC:%d)",
get_bits(0, 4, ps), get_bits(4, 1, ps),
get_bits(5, 1, ps), get_bits(6, 2, ps),
get_bits(18, 1, ps),
get_bits(8, 4, ps), get_bits(16, 2, ps));
/* FIXME: legacy xtensa port reported "HW" exception
* for all unhandled exceptions, which seems incorrect
* as these are software errors. Should clean this
* up.
*/
z_xtensa_fatal_error(reason,
(void *)interrupted_stack);
}
return return_to(interrupted_stack);
}
#if defined(CONFIG_GDBSTUB)
void *xtensa_debugint_c(int *interrupted_stack)
{
extern void z_gdb_isr(z_arch_esf_t *esf);
z_gdb_isr((void *)interrupted_stack);
return return_to(interrupted_stack);
}
#endif
int z_xtensa_irq_is_enabled(unsigned int irq)
{
uint32_t ie;
__asm__ volatile("rsr.intenable %0" : "=r"(ie));
return (ie & (1 << irq)) != 0U;
}