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Diffstat (limited to 'arch/sh/boards/saturn/smp.c')
-rw-r--r-- | arch/sh/boards/saturn/smp.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/sh/boards/saturn/smp.c b/arch/sh/boards/saturn/smp.c new file mode 100644 index 000000000000..76460918c9cd --- /dev/null +++ b/arch/sh/boards/saturn/smp.c @@ -0,0 +1,68 @@ +/* + * arch/sh/boards/saturn/smp.c + * + * SMP support for the Sega Saturn. + * + * Copyright (c) 2002 Paul Mundt + * + * Released under the terms of the GNU GPL v2.0. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/smp.h> + +#include <asm/saturn/smpc.h> + +extern void start_secondary(void); + +void __smp_send_ipi(unsigned int cpu, unsigned int action) +{ + /* Nothing here yet .. */ +} + +unsigned int __smp_probe_cpus(void) +{ + /* + * This is just a straightforward master/slave configuration, + * and probing isn't really supported.. + */ + return 2; +} + +/* + * We're only allowed to do byte-access to SMPC registers. In + * addition to which, we treat them as write-only, since + * reading from them will return undefined data. + */ +static inline void smpc_slave_stop(unsigned int cpu) +{ + smpc_barrier(); + ctrl_outb(1, SMPC_STATUS); + + ctrl_outb(SMPC_CMD_SSHOFF, SMPC_COMMAND); + smpc_barrier(); +} + +static inline void smpc_slave_start(unsigned int cpu) +{ + ctrl_outb(1, SMPC_STATUS); + ctrl_outb(SMPC_CMD_SSHON, SMPC_COMMAND); + + smpc_barrier(); +} + +void __smp_slave_init(unsigned int cpu) +{ + register unsigned long vbr; + void **entry; + + __asm__ __volatile__ ("stc vbr, %0\n\t" : "=r" (vbr)); + entry = (void **)(vbr + 0x310 + 0x94); + + smpc_slave_stop(cpu); + + *(void **)entry = (void *)start_secondary; + + smpc_slave_start(cpu); +} + |