From 16c358e96e0597b7d60754547166ad05ecc6d93d Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Tue, 11 Mar 2014 10:36:00 +0100 Subject: target-sparc: Add and use CPU_FEATURE_CASA MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The LEON3 processor has support for the CASA instruction which is normally only available for SPARC V9 processors. Binutils 2.24 and GCC 4.9 will support this instruction for LEON3. GCC uses it to generate C11 atomic operations. The CAS synthetic instruction uses an ASI of 0x80. If TARGET_SPARC64 is not defined use a supervisor data load/store for an ASI of 0x80 in helper_ld_asi()/helper_st_asi(). The supervisor data load/store was choosen according to the LEON3 documentation. The ASI 0x80 is defined in the SPARC V9 manual, Table 12—Address Space Identifiers (ASIs). Here we have: 0x80, ASI_PRIMARY, Unrestricted access, Primary address space. Tested with the following program: #include #include void test(void) { atomic_int a; int e; _Bool b; atomic_store(&a, 1); e = 1; b = atomic_compare_exchange_strong(&a, &e, 2); assert(b); assert(atomic_load(&a) == 2); atomic_store(&a, 3); e = 4; b = atomic_compare_exchange_strong(&a, &e, 5); assert(!b); assert(atomic_load(&a) == 3); } Tested also on a NGMP board with a LEON4 processor. Reviewed-by: Fabien Chouteau Reviewed-by: Andreas Färber Tested-by: Mark Cave-Ayland Reviewed-by: Richard Henderson Signed-off-by: Sebastian Huber Signed-off-by: Mark Cave-Ayland --- target-sparc/cpu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'target-sparc/cpu.c') diff --git a/target-sparc/cpu.c b/target-sparc/cpu.c index e7f878e..5806e59 100644 --- a/target-sparc/cpu.c +++ b/target-sparc/cpu.c @@ -458,7 +458,8 @@ static const sparc_def_t sparc_defs[] = { .mmu_trcr_mask = 0xffffffff, .nwindows = 8, .features = CPU_DEFAULT_FEATURES | CPU_FEATURE_TA0_SHUTDOWN | - CPU_FEATURE_ASR17 | CPU_FEATURE_CACHE_CTRL | CPU_FEATURE_POWERDOWN, + CPU_FEATURE_ASR17 | CPU_FEATURE_CACHE_CTRL | CPU_FEATURE_POWERDOWN | + CPU_FEATURE_CASA, }, #endif }; -- cgit v1.1