From 45ed285b54930767937deb0eaf718b1d08c3c475 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Thu, 8 Mar 2007 18:12:17 +0900 Subject: sh: speculative execution support for SH7780. SH7780 has a speculative execution mode where it can speculatively perform an instruction fetch for subroutine returns, this allows it to be enabled. There are some various pitfalls associated with this mode, so it's left as depending on CONFIG_EXPERIMENTAL and not enabled by default. Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/init.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'arch/sh/kernel') diff --git a/arch/sh/kernel/cpu/init.c b/arch/sh/kernel/cpu/init.c index 726acfc..6451ad6 100644 --- a/arch/sh/kernel/cpu/init.c +++ b/arch/sh/kernel/cpu/init.c @@ -41,6 +41,23 @@ __setup("no" __stringify(x), x##_setup); onchip_setup(fpu); onchip_setup(dsp); +#ifdef CONFIG_SPECULATIVE_EXECUTION +#define CPUOPM 0xff2f0000 +#define CPUOPM_RABD (1 << 5) + +static void __init speculative_execution_init(void) +{ + /* Clear RABD */ + ctrl_outl(ctrl_inl(CPUOPM) & ~CPUOPM_RABD, CPUOPM); + + /* Flush the update */ + (void)ctrl_inl(CPUOPM); + ctrl_barrier(); +} +#else +#define speculative_execution_init() do { } while (0) +#endif + /* * Generic first-level cache init */ @@ -261,4 +278,6 @@ asmlinkage void __init sh_cpu_init(void) */ ubc_wakeup(); #endif + + speculative_execution_init(); } -- cgit v1.1