From 93a739d4a1c34c9dbb96ced4fbeaa18e02000b6a Mon Sep 17 00:00:00 2001 From: Manjunath Matti Date: Tue, 5 Dec 2023 06:38:47 -0600 Subject: powerpc: Add space for HWCAP3/HWCAP4 in the TCB for future Power. This patch reserves space for HWCAP3/HWCAP4 in the TCB of powerpc. These hardware capabilities bits will be used by future Power architectures. Versioned symbol '__parse_hwcap_3_4_and_convert_at_platform' advertises the availability of the new HWCAP3/HWCAP4 data in the TCB. This is an ABI change for GLIBC 2.39. Suggested-by: Peter Bergner Reviewed-by: Peter Bergner --- sysdeps/powerpc/Versions | 5 +++++ sysdeps/powerpc/hwcapinfo.c | 5 +++++ sysdeps/powerpc/nptl/tcb-offsets.sym | 1 + sysdeps/powerpc/nptl/tls.h | 13 ++++++++++++- 4 files changed, 23 insertions(+), 1 deletion(-) (limited to 'sysdeps/powerpc') diff --git a/sysdeps/powerpc/Versions b/sysdeps/powerpc/Versions index cca8fd2..575f731 100644 --- a/sysdeps/powerpc/Versions +++ b/sysdeps/powerpc/Versions @@ -24,4 +24,9 @@ ld { # and AT_PLATFORM data should be stored into the TCB. __parse_hwcap_and_convert_at_platform; } + GLIBC_2.39 { + # Symbol used to version control when the ABI started to specify that + # HWCAP3 and HWCAP4 are stored in the TCB. + __parse_hwcap_3_4_and_convert_at_platform; + } } diff --git a/sysdeps/powerpc/hwcapinfo.c b/sysdeps/powerpc/hwcapinfo.c index f2c473c..a4d5aa1 100644 --- a/sysdeps/powerpc/hwcapinfo.c +++ b/sysdeps/powerpc/hwcapinfo.c @@ -70,11 +70,14 @@ __tcb_parse_hwcap_and_convert_at_platform (void) /* Consolidate both HWCAP and HWCAP2 into a single doubleword so that we can read both in a single load later. */ __tcb.hwcap = (h1 << 32) | (h2 & 0xffffffff); + __tcb.hwcap_extn = 0x0; } #if IS_IN (rtld) versioned_symbol (ld, __tcb_parse_hwcap_and_convert_at_platform, \ __parse_hwcap_and_convert_at_platform, GLIBC_2_23); +versioned_symbol (ld, __tcb_parse_hwcap_and_convert_at_platform, \ + __parse_hwcap_3_4_and_convert_at_platform, GLIBC_2_39); #endif /* Export __parse_hwcap_and_convert_at_platform in libc.a. This is used by @@ -83,4 +86,6 @@ versioned_symbol (ld, __tcb_parse_hwcap_and_convert_at_platform, \ #ifndef SHARED weak_alias (__tcb_parse_hwcap_and_convert_at_platform, \ __parse_hwcap_and_convert_at_platform); +weak_alias (__tcb_parse_hwcap_and_convert_at_platform, \ + __parse_hwcap_3_4_and_convert_at_platform); #endif diff --git a/sysdeps/powerpc/nptl/tcb-offsets.sym b/sysdeps/powerpc/nptl/tcb-offsets.sym index 4c01615..9b29fe8 100644 --- a/sysdeps/powerpc/nptl/tcb-offsets.sym +++ b/sysdeps/powerpc/nptl/tcb-offsets.sym @@ -26,3 +26,4 @@ TCB_AT_PLATFORM (offsetof (tcbhead_t, at_platform) - TLS_TCB_OFFSET - sizeof(t PADDING (offsetof (tcbhead_t, padding) - TLS_TCB_OFFSET - sizeof(tcbhead_t)) #endif TCB_HWCAP (offsetof (tcbhead_t, hwcap) - TLS_TCB_OFFSET - sizeof (tcbhead_t)) +TCB_HWCAP_EXTN (offsetof (tcbhead_t, hwcap_extn) - TLS_TCB_OFFSET - sizeof (tcbhead_t)) diff --git a/sysdeps/powerpc/nptl/tls.h b/sysdeps/powerpc/nptl/tls.h index a668798..3f8eca5 100644 --- a/sysdeps/powerpc/nptl/tls.h +++ b/sysdeps/powerpc/nptl/tls.h @@ -64,6 +64,9 @@ are private. */ typedef struct { + /* Reservation for HWCAP3 and HWCAP4 data. To be accessed by GCC in + __builtin_cpu_supports(), so it is a part of the public ABI. */ + uint64_t hwcap_extn; /* Reservation for HWCAP data. To be accessed by GCC in __builtin_cpu_supports(), so it is a part of public ABI. */ uint64_t hwcap; @@ -138,6 +141,7 @@ typedef struct ({ \ __thread_register = (void *) (tcbp) + TLS_TCB_OFFSET; \ THREAD_SET_HWCAP (__tcb.hwcap); \ + THREAD_SET_HWCAP_EXTN (__tcb.hwcap_extn); \ THREAD_SET_AT_PLATFORM (__tcb.at_platform); \ true; \ }) @@ -147,6 +151,8 @@ typedef struct void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE; \ (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].hwcap) = \ THREAD_GET_HWCAP (); \ + (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].hwcap_extn) = \ + THREAD_GET_HWCAP_EXTN (); \ (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].at_platform) = \ THREAD_GET_AT_PLATFORM (); @@ -189,12 +195,17 @@ typedef struct + TLS_PRE_TCB_SIZE))[-1].pointer_guard \ = THREAD_GET_POINTER_GUARD()) -/* hwcap field in TCB head. */ +/* hwcap & hwcap_extn fields in TCB head. */ # define THREAD_GET_HWCAP() \ (((tcbhead_t *) ((char *) __thread_register \ - TLS_TCB_OFFSET))[-1].hwcap) +# define THREAD_GET_HWCAP_EXTN() \ + (((tcbhead_t *) ((char *) __thread_register \ + - TLS_TCB_OFFSET))[-1].hwcap_extn) # define THREAD_SET_HWCAP(value) \ (THREAD_GET_HWCAP () = (value)) +# define THREAD_SET_HWCAP_EXTN(value) \ + (THREAD_GET_HWCAP_EXTN () = (value)) /* at_platform field in TCB head. */ # define THREAD_GET_AT_PLATFORM() \ -- cgit v1.1