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author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/blackfin/kernel/reboot.c |
Initial import
Diffstat (limited to 'arch/blackfin/kernel/reboot.c')
-rw-r--r-- | arch/blackfin/kernel/reboot.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/reboot.c b/arch/blackfin/kernel/reboot.c new file mode 100644 index 000000000..c4f50a328 --- /dev/null +++ b/arch/blackfin/kernel/reboot.c @@ -0,0 +1,115 @@ +/* + * arch/blackfin/kernel/reboot.c - handle shutdown/reboot + * + * Copyright 2004-2007 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/interrupt.h> +#include <asm/bfin-global.h> +#include <asm/reboot.h> +#include <asm/bfrom.h> + +/* A system soft reset makes external memory unusable so force + * this function into L1. We use the compiler ssync here rather + * than SSYNC() because it's safe (no interrupts and such) and + * we save some L1. We do not need to force sanity in the SYSCR + * register as the BMODE selection bit is cleared by the soft + * reset while the Core B bit (on dual core parts) is cleared by + * the core reset. + */ +__attribute__ ((__l1_text__, __noreturn__)) +static void bfin_reset(void) +{ +#ifndef CONFIG_BF60x + if (!ANOMALY_05000353 && !ANOMALY_05000386) + bfrom_SoftReset((void *)(L1_SCRATCH_START + L1_SCRATCH_LENGTH - 20)); + + /* Wait for completion of "system" events such as cache line + * line fills so that we avoid infinite stalls later on as + * much as possible. This code is in L1, so it won't trigger + * any such event after this point in time. + */ + __builtin_bfin_ssync(); + + /* Initiate System software reset. */ + bfin_write_SWRST(0x7); + + /* Due to the way reset is handled in the hardware, we need + * to delay for 10 SCLKS. The only reliable way to do this is + * to calculate the CCLK/SCLK ratio and multiply 10. For now, + * we'll assume worse case which is a 1:15 ratio. + */ + asm( + "LSETUP (1f, 1f) LC0 = %0\n" + "1: nop;" + : + : "a" (15 * 10) + : "LC0", "LB0", "LT0" + ); + + /* Clear System software reset */ + bfin_write_SWRST(0); + + /* The BF526 ROM will crash during reset */ +#if defined(__ADSPBF522__) || defined(__ADSPBF524__) || defined(__ADSPBF526__) + /* Seems to be fixed with newer parts though ... */ + if (__SILICON_REVISION__ < 1 && bfin_revid() < 1) + bfin_read_SWRST(); +#endif + /* Wait for the SWRST write to complete. Cannot rely on SSYNC + * though as the System state is all reset now. + */ + asm( + "LSETUP (1f, 1f) LC1 = %0\n" + "1: nop;" + : + : "a" (15 * 1) + : "LC1", "LB1", "LT1" + ); + + while (1) + /* Issue core reset */ + asm("raise 1"); +#else + while (1) + bfin_write_RCU0_CTL(0x1); +#endif +} + +__attribute__((weak)) +void native_machine_restart(char *cmd) +{ +} + +void machine_restart(char *cmd) +{ + native_machine_restart(cmd); + if (smp_processor_id()) + smp_call_function((void *)bfin_reset, 0, 1); + else + bfin_reset(); +} + +__attribute__((weak)) +void native_machine_halt(void) +{ + idle_with_irq_disabled(); +} + +void machine_halt(void) +{ + native_machine_halt(); +} + +__attribute__((weak)) +void native_machine_power_off(void) +{ + idle_with_irq_disabled(); +} + +void machine_power_off(void) +{ + native_machine_power_off(); +} |