diff options
| -rw-r--r-- | arch/arm/Kconfig | 4 | ||||
| -rw-r--r-- | arch/arm/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/iwmmxt.S | 55 | ||||
| -rw-r--r-- | arch/arm/kernel/pj4-cp0.c | 94 |
4 files changed, 139 insertions, 15 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index d56d21c0573b..e2c79a24d3c6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -999,8 +999,8 @@ source arch/arm/mm/Kconfig config IWMMXT bool "Enable iWMMXt support" - depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK - default y if PXA27x || PXA3xx || ARCH_MMP + depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 + default y if PXA27x || PXA3xx || PXA95x || ARCH_MMP help Enable support for iWMMXt context switching at run time if running on a CPU that supports it. diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 5b9b268f4fbb..b0f11fa7a4b4 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -50,6 +50,7 @@ AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312 obj-$(CONFIG_CPU_XSCALE) += xscale-cp0.o obj-$(CONFIG_CPU_XSC3) += xscale-cp0.o obj-$(CONFIG_CPU_MOHAWK) += xscale-cp0.o +obj-$(CONFIG_CPU_PJ4) += pj4-cp0.o obj-$(CONFIG_IWMMXT) += iwmmxt.o obj-$(CONFIG_CPU_HAS_PMU) += pmu.o obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S index b63b528f22a6..7fa3bb0d2397 100644 --- a/arch/arm/kernel/iwmmxt.S +++ b/arch/arm/kernel/iwmmxt.S @@ -19,6 +19,14 @@ #include <asm/thread_info.h> #include <asm/asm-offsets.h> +#if defined(CONFIG_CPU_PJ4) +#define PJ4(code...) code +#define XSC(code...) +#else +#define PJ4(code...) +#define XSC(code...) code +#endif + #define MMX_WR0 (0x00) #define MMX_WR1 (0x08) #define MMX_WR2 (0x10) @@ -58,11 +66,17 @@ ENTRY(iwmmxt_task_enable) - mrc p15, 0, r2, c15, c1, 0 - tst r2, #0x3 @ CP0 and CP1 accessible? + XSC(mrc p15, 0, r2, c15, c1, 0) + PJ4(mrc p15, 0, r2, c1, c0, 2) + @ CP0 and CP1 accessible? + XSC(tst r2, #0x3) + PJ4(tst r2, #0xf) movne pc, lr @ if so no business here - orr r2, r2, #0x3 @ enable access to CP0 and CP1 - mcr p15, 0, r2, c15, c1, 0 + @ enable access to CP0 and CP1 + XSC(orr r2, r2, #0x3) + XSC(mcr p15, 0, r2, c15, c1, 0) + PJ4(orr r2, r2, #0xf) + PJ4(mcr p15, 0, r2, c1, c0, 2) ldr r3, =concan_owner add r0, r10, #TI_IWMMXT_STATE @ get task Concan save area @@ -179,17 +193,26 @@ ENTRY(iwmmxt_task_disable) teqne r1, r2 @ or specified one? bne 1f @ no: quit - mrc p15, 0, r4, c15, c1, 0 - orr r4, r4, #0x3 @ enable access to CP0 and CP1 - mcr p15, 0, r4, c15, c1, 0 + @ enable access to CP0 and CP1 + XSC(mrc p15, 0, r4, c15, c1, 0) + XSC(orr r4, r4, #0xf) + XSC(mcr p15, 0, r4, c15, c1, 0) + PJ4(mrc p15, 0, r4, c1, c0, 2) + PJ4(orr r4, r4, #0x3) + PJ4(mcr p15, 0, r4, c1, c0, 2) + mov r0, #0 @ nothing to load str r0, [r3] @ no more current owner mrc p15, 0, r2, c2, c0, 0 mov r2, r2 @ cpwait bl concan_save - bic r4, r4, #0x3 @ disable access to CP0 and CP1 - mcr p15, 0, r4, c15, c1, 0 + @ disable access to CP0 and CP1 + XSC(bic r4, r4, #0x3) + XSC(mcr p15, 0, r4, c15, c1, 0) + PJ4(bic r4, r4, #0xf) + PJ4(mcr p15, 0, r4, c1, c0, 2) + mrc p15, 0, r2, c2, c0, 0 mov r2, r2 @ cpwait @@ -277,8 +300,11 @@ ENTRY(iwmmxt_task_restore) */ ENTRY(iwmmxt_task_switch) - mrc p15, 0, r1, c15, c1, 0 - tst r1, #0x3 @ CP0 and CP1 accessible? + XSC(mrc p15, 0, r1, c15, c1, 0) + PJ4(mrc p15, 0, r1, c1, c0, 2) + @ CP0 and CP1 accessible? + XSC(tst r1, #0x3) + PJ4(tst r1, #0xf) bne 1f @ yes: block them for next task ldr r2, =concan_owner @@ -287,8 +313,11 @@ ENTRY(iwmmxt_task_switch) teq r2, r3 @ next task owns it? movne pc, lr @ no: leave Concan disabled -1: eor r1, r1, #3 @ flip Concan access - mcr p15, 0, r1, c15, c1, 0 +1: @ flip Conan access + XSC(eor r1, r1, #0x3) + XSC(mcr p15, 0, r1, c15, c1, 0) + PJ4(eor r1, r1, #0xf) + PJ4(mcr p15, 0, r1, c1, c0, 2) mrc p15, 0, r1, c2, c0, 0 sub pc, lr, r1, lsr #32 @ cpwait and return diff --git a/arch/arm/kernel/pj4-cp0.c b/arch/arm/kernel/pj4-cp0.c new file mode 100644 index 000000000000..a4b1b0748fd3 --- /dev/null +++ b/arch/arm/kernel/pj4-cp0.c @@ -0,0 +1,94 @@ +/* + * linux/arch/arm/kernel/pj4-cp0.c + * + * PJ4 iWMMXt coprocessor context switching and handling + * + * Copyright (c) 2010 Marvell International Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/io.h> +#include <asm/thread_notify.h> + +static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t) +{ + struct thread_info *thread = t; + + switch (cmd) { + case THREAD_NOTIFY_FLUSH: + /* + * flush_thread() zeroes thread->fpstate, so no need + * to do anything here. + * + * FALLTHROUGH: Ensure we don't try to overwrite our newly + * initialised state information on the first fault. + */ + + case THREAD_NOTIFY_EXIT: + iwmmxt_task_release(thread); + break; + + case THREAD_NOTIFY_SWITCH: + iwmmxt_task_switch(thread); + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block iwmmxt_notifier_block = { + .notifier_call = iwmmxt_do, +}; + + +static u32 __init pj4_cp_access_read(void) +{ + u32 value; + + __asm__ __volatile__ ( + "mrc p15, 0, %0, c1, c0, 2\n\t" + : "=r" (value)); + return value; +} + +static void __init pj4_cp_access_write(u32 value) +{ + u32 temp; + + __asm__ __volatile__ ( + "mcr p15, 0, %1, c1, c0, 2\n\t" + "mrc p15, 0, %0, c1, c0, 2\n\t" + "mov %0, %0\n\t" + "sub pc, pc, #4\n\t" + : "=r" (temp) : "r" (value)); +} + + +/* + * Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy + * switch code handle iWMMXt context switching. + */ +static int __init pj4_cp0_init(void) +{ + u32 cp_access; + + cp_access = pj4_cp_access_read() & ~0xf; + pj4_cp_access_write(cp_access); + + printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n"); + elf_hwcap |= HWCAP_IWMMXT; + thread_register_notifier(&iwmmxt_notifier_block); + + return 0; +} + +late_initcall(pj4_cp0_init); |