From: Tim Newsome Date: Mon, 28 Aug 2017 19:43:08 +0000 (-0700) Subject: Forgot to add this file. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1bfc5f01ffb5bb838416a621770ae9d102c9a715;p=riscv-tests.git Forgot to add this file. --- diff --git a/debug/programs/multicore.c b/debug/programs/multicore.c new file mode 100644 index 0000000..d7dd845 --- /dev/null +++ b/debug/programs/multicore.c @@ -0,0 +1,81 @@ +#include + +typedef struct { + int counter; +} atomic_t; + +static inline int atomic_xchg(atomic_t *v, int n) +{ + register int c; + + __asm__ __volatile__ ( + "amoswap.w.aqrl %0, %2, %1" + : "=r" (c), "+A" (v->counter) + : "r" (n)); + return c; +} + +#define csr_read(csr) \ +({ \ + register unsigned long __v; \ + __asm__ __volatile__ ("csrr %0, " #csr \ + : "=r" (__v)); \ + __v; \ +}) + +static inline void mb(void) +{ + __asm__ __volatile__ ("fence"); +} + +void get_lock(atomic_t *lock) +{ + while (atomic_xchg(lock, 1) == 1) + ; + mb(); +} + +void put_lock(atomic_t *lock) +{ + mb(); + atomic_xchg(lock, 0); +} + +static atomic_t buf_lock = { .counter = 0 }; +static char buf[32]; +static int buf_initialized; +static unsigned hart_count[2]; + +static const char case_bit = 'a' - 'A'; +volatile int initialized; + +int main() +{ + uint32_t hartid = csr_read(mhartid); + hart_count[hartid] = 0; + + while (1) { + get_lock(&buf_lock); + hart_count[hartid]++; + + if (!buf_initialized) { + for (unsigned i = 0; i < sizeof(buf); i++) { + buf[i] = 'A' + (i % 26); + } + buf_initialized = 1; + } + + char first = buf[0]; + int offset = (first & ~0x20) - 'A'; + for (unsigned i = 0; i < sizeof(buf); i++) { + while (buf[i] != (first - offset + ((offset + i) % 26))) + ; + + if (hartid & 1) + buf[i] = 'A' + ((i + hartid + hart_count[hartid]) % 26); + else + buf[i] = 'a' + ((i + hartid + hart_count[hartid]) % 26); + } + put_lock(&buf_lock); + } +}