diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/cpuinfo-riscv.c | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/util/cpuinfo-riscv.c b/util/cpuinfo-riscv.c index 8cacc67645..971c924012 100644 --- a/util/cpuinfo-riscv.c +++ b/util/cpuinfo-riscv.c @@ -4,6 +4,7 @@ */ #include "qemu/osdep.h" +#include "qemu/host-utils.h" #include "host/cpuinfo.h" #ifdef CONFIG_ASM_HWPROBE_H @@ -13,6 +14,7 @@ #endif unsigned cpuinfo; +unsigned riscv_lg2_vlenb; static volatile sig_atomic_t got_sigill; static void sigill_handler(int signo, siginfo_t *si, void *data) @@ -34,7 +36,7 @@ static void sigill_handler(int signo, siginfo_t *si, void *data) /* Called both as constructor and (possibly) via other constructors. */ unsigned __attribute__((constructor)) cpuinfo_init(void) { - unsigned left = CPUINFO_ZBA | CPUINFO_ZBB | CPUINFO_ZICOND; + unsigned left = CPUINFO_ZBA | CPUINFO_ZBB | CPUINFO_ZICOND | CPUINFO_ZVE64X; unsigned info = cpuinfo; if (info) { @@ -51,6 +53,10 @@ unsigned __attribute__((constructor)) cpuinfo_init(void) #if defined(__riscv_arch_test) && defined(__riscv_zicond) info |= CPUINFO_ZICOND; #endif +#if defined(__riscv_arch_test) && \ + (defined(__riscv_vector) || defined(__riscv_zve64x)) + info |= CPUINFO_ZVE64X; +#endif left &= ~info; #ifdef CONFIG_ASM_HWPROBE_H @@ -70,10 +76,21 @@ unsigned __attribute__((constructor)) cpuinfo_init(void) info |= pair.value & RISCV_HWPROBE_EXT_ZICOND ? CPUINFO_ZICOND : 0; left &= ~CPUINFO_ZICOND; #endif + /* For rv64, V is Zve64d, a superset of Zve64x. */ + info |= pair.value & RISCV_HWPROBE_IMA_V ? CPUINFO_ZVE64X : 0; +#ifdef RISCV_HWPROBE_EXT_ZVE64X + info |= pair.value & RISCV_HWPROBE_EXT_ZVE64X ? CPUINFO_ZVE64X : 0; +#endif } } #endif /* CONFIG_ASM_HWPROBE_H */ + /* + * We only detect support for vectors with hwprobe. All kernels with + * support for vectors in userspace also support the hwprobe syscall. + */ + left &= ~CPUINFO_ZVE64X; + if (left) { struct sigaction sa_old, sa_new; @@ -113,6 +130,21 @@ unsigned __attribute__((constructor)) cpuinfo_init(void) assert(left == 0); } + if (info & CPUINFO_ZVE64X) { + /* + * We are guaranteed by RVV-1.0 that VLEN is a power of 2. + * We are guaranteed by Zve64x that VLEN >= 64, and that + * EEW of {8,16,32,64} are supported. + */ + unsigned long vlenb; + /* csrr %0, vlenb */ + asm volatile(".insn i 0x73, 0x2, %0, zero, -990" : "=r"(vlenb)); + assert(vlenb >= 8); + assert(is_power_of_2(vlenb)); + /* Cache VLEN in a convenient form. */ + riscv_lg2_vlenb = ctz32(vlenb); + } + info |= CPUINFO_ALWAYS; cpuinfo = info; return info; |