From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54332) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eSX8G-0005jT-64 for qemu-devel@nongnu.org; Fri, 22 Dec 2017 18:53:41 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eSX8D-0003vG-3s for qemu-devel@nongnu.org; Fri, 22 Dec 2017 18:53:40 -0500 From: Michael Weiser Date: Fri, 22 Dec 2017 20:23:00 +0100 Message-Id: <20171222192300.46997-1-michael.weiser@gmx.de> Subject: [Qemu-devel] [RFC PATCH] target/arm: Fix stlxp for aarch64_be List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org Cc: Michael Weiser , Peter Maydell , qemu-devel@nongnu.org In big-endian mode, stlxp would not only store the individual doublewords big-endian but also swap them in memory. This does not correspond to how ldxp behaves nor how native code expects the result of stlxp to be stored in memory. Also, when comparing if the values in memory still match what was previously loaded by ldxp, stlxp would also swap the values loaded from memory, making the comparison against the previously loaded value fail always. With this change an aarch64_be Linux 4.14.4 kernel succeeds to boots up in system emulation mode. This change makes paired_cmpxchg64 helpers differ only in endianness handling. It might be possible to fold them into a single routine using variables and function pointers or get rid of them completely in favour of tcg_gen_-routines. Both is currently beyond my skill level, though. Signed-off-by: Michael Weiser --- target/arm/helper-a64.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/target/arm/helper-a64.c b/target/arm/helper-a64.c index b84ebcae6e..bab6446588 100644 --- a/target/arm/helper-a64.c +++ b/target/arm/helper-a64.c @@ -532,8 +532,8 @@ static uint64_t do_paired_cmpxchg64_be(CPUARMState *env, uint64_t addr, success = int128_eq(oldv, cmpv); if (success) { - stq_be_p(haddr + 0, int128_gethi(newv)); - stq_be_p(haddr + 1, int128_getlo(newv)); + stq_be_p(haddr + 0, int128_getlo(newv)); + stq_be_p(haddr + 1, int128_gethi(newv)); } helper_retaddr = 0; #else @@ -541,14 +541,14 @@ static uint64_t do_paired_cmpxchg64_be(CPUARMState *env, uint64_t addr, TCGMemOpIdx oi0 = make_memop_idx(MO_BEQ | MO_ALIGN_16, mem_idx); TCGMemOpIdx oi1 = make_memop_idx(MO_BEQ, mem_idx); - o1 = helper_be_ldq_mmu(env, addr + 0, oi0, ra); - o0 = helper_be_ldq_mmu(env, addr + 8, oi1, ra); + o0 = helper_be_ldq_mmu(env, addr + 0, oi0, ra); + o1 = helper_be_ldq_mmu(env, addr + 8, oi1, ra); oldv = int128_make128(o0, o1); success = int128_eq(oldv, cmpv); if (success) { - helper_be_stq_mmu(env, addr + 0, int128_gethi(newv), oi1, ra); - helper_be_stq_mmu(env, addr + 8, int128_getlo(newv), oi1, ra); + helper_be_stq_mmu(env, addr + 0, int128_getlo(newv), oi1, ra); + helper_be_stq_mmu(env, addr + 8, int128_gethi(newv), oi1, ra); } #endif } -- 2.15.1