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PP502x: Get switch_thread back out of IRAM and devise a better core wakeup system that's not timing dependant. Hopefully something simpler will be found or devised eventually that meets all requirements. Rename mailbox-related registers.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15179 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Michael Sevakis 2007-10-18 01:26:50 +00:00
parent fffc257897
commit a443614dd2
2 changed files with 102 additions and 54 deletions
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131
firmware/thread.c
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@ -387,13 +387,6 @@ void corelock_unlock(struct corelock *cl)
#endif /* CONFIG_CORELOCK == SW_CORELOCK */
#ifdef CPU_PP502x
/* Some code relies on timing */
void switch_thread(struct thread_entry *old) ICODE_ATTR;
void core_wake(IF_COP_VOID(unsigned int othercore)) ICODE_ATTR;
void core_idle(void) ICODE_ATTR;
#endif
/*---------------------------------------------------------------------------
* Put core in a power-saving state if waking list wasn't repopulated and if
* no other core requested a wakeup for it to perform a task.
@ -403,34 +396,59 @@ static inline void core_sleep(IF_COP(unsigned int core,) struct thread_entry **w
{
#if NUM_CORES > 1
#ifdef CPU_PP502x
#if 1
/* Disabling IRQ and FIQ is important to making the fixed-time sequence
* non-interruptable */
asm volatile (
"mrs r2, cpsr \n" /* Disable IRQ, FIQ */
"orr r2, r2, #0xc0 \n"
"msr cpsr_c, r2 \n"
"ldr r0, [%[w]] \n" /* Check *waking */
"cmp r0, #0 \n" /* != NULL -> exit */
"bne 1f \n"
/* ------ fixed-time sequence ----- */ /* Can this be relied upon? */
"ldr r0, [%[ms], %[oc], lsl #2] \n" /* Stay-awake requested? */
"mov r1, #0x80000000 \n"
"tst r0, #1 \n"
"streq r1, [%[ct], %[c], lsl #2] \n" /* Sleep if not */
"nop \n"
"mov r0, #0 \n"
"str r0, [%[ct], %[c], lsl #2] \n" /* Clear control reg */
/* -------------------------------- */
"1: \n"
"mov r0, #1 \n"
"add r1, %[ms], #8 \n"
"str r0, [r1, %[oc], lsl #2] \n" /* Clear mailbox */
"mov r0, #4 \n" /* r0 = 0x4 << core */
"mov r0, r0, lsl %[c] \n"
"str r0, [%[mbx], #4] \n" /* signal intent to sleep */
"ldr r1, [%[waking]] \n" /* *waking == NULL ? */
"cmp r1, #0 \n"
"ldreq r1, [%[mbx], #0] \n" /* && !(MBX_MSG_STAT & (0x10<<core)) ? */
"tsteq r1, r0, lsl #2 \n"
"moveq r1, #0x80000000 \n" /* Then sleep */
"streq r1, [%[ctl], %[c], lsl #2] \n"
"moveq r1, #0 \n" /* Clear control reg */
"streq r1, [%[ctl], %[c], lsl #2] \n"
"orr r1, r0, r0, lsl #2 \n" /* Signal intent to wake - clear wake flag */
"str r1, [%[mbx], #8] \n"
"1: \n" /* Wait for wake procedure to finish */
"ldr r1, [%[mbx], #0] \n"
"tst r1, r0, lsr #2 \n"
"bne 1b \n"
"bic r2, r2, #0xc0 \n" /* Enable interrupts */
"msr cpsr_c, r2 \n"
:
: [ct]"r"(&PROC_CTL(CPU)), [ms]"r"(&PROC_MESSAGE(CPU)),
[c]"r" (core), [oc]"r"(1-core), [w]"r"(waking)
:
: [ctl]"r"(&PROC_CTL(CPU)), [mbx]"r"(MBX_BASE),
[waking]"r"(waking), [c]"r"(core)
: "r0", "r1", "r2");
#else /* C version for reference */
/* Disable IRQ, FIQ */
set_interrupt_status(IRQ_FIQ_DISABLED, IRQ_FIQ_STATUS);
/* Signal intent to sleep */
MBX_MSG_SET = 0x4 << core;
/* Something waking or other processor intends to wake us? */
if (*waking == NULL && (MBX_MSG_STAT & (0x10 << core)) == 0)
{
PROC_CTL(core) = PROC_SLEEP; nop; /* Snooze */
PROC_CTL(core) = 0; /* Clear control reg */
}
/* Signal wake - clear wake flag */
MBX_MSG_CLR = 0x14 << core;
/* Wait for other processor to finish wake procedure */
while (MBX_MSG_STAT & (0x1 << core));
/* Enable IRQ, FIQ */
set_interrupt_status(IRQ_FIQ_ENABLED, IRQ_FIQ_STATUS);
#endif /* ASM/C selection */
#else
/* TODO: PP5002 */
#endif /* CONFIG_CPU == */
@ -454,26 +472,52 @@ void core_wake(IF_COP_VOID(unsigned int othercore))
#if NUM_CORES == 1
/* No wakey - core already wakey */
#elif defined (CPU_PP502x)
#if 1
/* avoid r0 since that contains othercore */
asm volatile (
"mrs r2, cpsr \n"
"orr r1, r2, #0xc0 \n"
"msr cpsr_c, r1 \n"
"mov r1, #1 \n"
/* ------ fixed-time sequence ----- */ /* Can this be relied upon? */
"str r1, [%[ms], %[oc], lsl #2] \n" /* Send stay-awake message */
"nop \n"
"nop \n"
"ldr r1, [%[ct], %[oc], lsl #2] \n" /* Wake other core if asleep */
"tst r1, #0x80000000 \n"
"bic r1, r1, #0x80000000 \n"
"strne r1, [%[ct], %[oc], lsl #2] \n"
/* -------------------------------- */
"msr cpsr_c, r2 \n"
"mrs r3, cpsr \n" /* Disable IRQ */
"orr r1, r3, #0x80 \n"
"msr cpsr_c, r1 \n"
"mov r2, #0x11 \n" /* r2 = (0x11 << othercore) */
"mov r2, r2, lsl %[oc] \n" /* Signal intent to wake othercore */
"str r2, [%[mbx], #4] \n"
"1: \n" /* If it intends to sleep, let it first */
"ldr r1, [%[mbx], #0] \n" /* (MSG_MSG_STAT & (0x4 << othercore)) != 0 ? */
"eor r1, r1, #0xc \n"
"tst r1, r2, lsr #2 \n"
"ldr r1, [%[ctl], %[oc], lsl #2] \n" /* && (PROC_CTL(othercore) & PROC_SLEEP) == 0 ? */
"tsteq r1, #0x80000000 \n"
"beq 1b \n" /* Wait for sleep or wake */
"tst r1, #0x80000000 \n" /* If sleeping, wake it */
"movne r1, #0x0 \n"
"strne r1, [%[ctl], %[oc], lsl #2] \n"
"mov r1, r2, lsr #4 \n"
"str r1, [%[mbx], #8] \n" /* Done with wake procedure */
"msr cpsr_c, r3 \n" /* Restore int status */
:
: [ct]"r"(&PROC_CTL(CPU)), [ms]"r"(&PROC_MESSAGE(CPU)),
[oc]"r" (othercore)
: "r1", "r2");
: [ctl]"r"(&PROC_CTL(CPU)), [mbx]"r"(MBX_BASE), [oc]"r" (othercore)
: "r1", "r2", "r3");
#else /* C version for reference */
/* Disable interrupts - avoid reentrancy from the tick */
int oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
/* Signal intent to wake other processor - set stay awake */
MBX_MSG_SET = 0x11 << othercore;
/* If it intends to sleep, wait until it does or aborts */
while ((MBX_MSG_STAT & (0x4 << othercore)) != 0 &&
(PROC_CTL(othercore) & PROC_SLEEP) == 0);
/* If sleeping, wake it up */
if (PROC_CTL(othercore) & PROC_SLEEP)
{
PROC_CTL(othercore) = 0;
}
/* Done with wake procedure */
MBX_MSG_CLR = 0x1 << othercore;
set_irq_level(oldlevel);
#endif /* ASM/C selection */
#else
PROC_CTL(othercore) = PROC_WAKE;
#endif
@ -2496,6 +2540,7 @@ void init_threads(void)
#if NUM_CORES > 1 /* This code path will not be run on single core targets */
/* TODO: HAL interface for this */
/* Wake up coprocessor and let it initialize kernel and threads */
MBX_MSG_CLR = 0x3f;
COP_CTL = PROC_WAKE;
/* Sleep until finished */
CPU_CTL = PROC_SLEEP;