From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754501AbbLIKSF (ORCPT ); Wed, 9 Dec 2015 05:18:05 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:45194 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754325AbbLIJj5 (ORCPT ); Wed, 9 Dec 2015 04:39:57 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Max Filippov , Luis Henriques Subject: [PATCH 3.16.y-ckt 052/126] xtensa: fixes for configs without loop option Date: Wed, 9 Dec 2015 09:37:02 +0000 Message-Id: <1449653896-5236-53-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> References: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt21 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Max Filippov commit 5029615e25dc5040beb065f36743c127a8e51497 upstream. Build-time fixes: - make lbeg/lend/lcount save/restore conditional on kernel entry; - don't clear lcount in platform_restart functions unconditionally. Run-time fixes: - use correct end of range register in __endla paired with __loopt, not the unused temporary register. This fixes .bss zero-initialization. Update comments in asmmacro.h; - don't clobber a10 in the usercopy that leads to access to unmapped memory. Signed-off-by: Max Filippov [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques --- arch/xtensa/include/asm/asmmacro.h | 7 ++++--- arch/xtensa/kernel/entry.S | 8 ++++++-- arch/xtensa/kernel/head.S | 2 +- arch/xtensa/lib/usercopy.S | 6 +++--- arch/xtensa/platforms/iss/setup.c | 2 ++ arch/xtensa/platforms/xt2000/setup.c | 2 ++ arch/xtensa/platforms/xtfpga/setup.c | 2 ++ 7 files changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/xtensa/include/asm/asmmacro.h b/arch/xtensa/include/asm/asmmacro.h index 755320f6e0bc..746dcc8b5abc 100644 --- a/arch/xtensa/include/asm/asmmacro.h +++ b/arch/xtensa/include/asm/asmmacro.h @@ -35,9 +35,10 @@ * __loop as * restart loop. 'as' register must not have been modified! * - * __endla ar, at, incr + * __endla ar, as, incr * ar start address (modified) - * as scratch register used by macro + * as scratch register used by __loops/__loopi macros or + * end address used by __loopt macro * inc increment */ @@ -97,7 +98,7 @@ .endm /* - * loop from ar to ax + * loop from ar to as */ .macro __loopt ar, as, at, incr_log2 diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index cf8a354fa628..232dbf41df34 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -335,8 +335,10 @@ common_exception: s32i a2, a1, PT_SYSCALL movi a2, 0 s32i a3, a1, PT_EXCVADDR +#if XCHAL_HAVE_LOOPS xsr a2, lcount s32i a2, a1, PT_LCOUNT +#endif /* It is now save to restore the EXC_TABLE_FIXUP variable. */ @@ -368,11 +370,12 @@ common_exception: s32i a3, a1, PT_PS # save ps /* Save lbeg, lend */ - +#if XCHAL_HAVE_LOOPS rsr a2, lbeg rsr a3, lend s32i a2, a1, PT_LBEG s32i a3, a1, PT_LEND +#endif /* Save SCOMPARE1 */ @@ -664,13 +667,14 @@ common_exception_exit: wsr a3, sar /* Restore LBEG, LEND, LCOUNT */ - +#if XCHAL_HAVE_LOOPS l32i a2, a1, PT_LBEG l32i a3, a1, PT_LEND wsr a2, lbeg l32i a2, a1, PT_LCOUNT wsr a3, lend wsr a2, lcount +#endif /* We control single stepping through the ICOUNTLEVEL register. */ diff --git a/arch/xtensa/kernel/head.S b/arch/xtensa/kernel/head.S index aeeb3cc8a410..384a497d8566 100644 --- a/arch/xtensa/kernel/head.S +++ b/arch/xtensa/kernel/head.S @@ -244,7 +244,7 @@ ENTRY(_startup) __loopt a2, a3, a4, 2 s32i a0, a2, 0 - __endla a2, a4, 4 + __endla a2, a3, 4 #if XCHAL_DCACHE_IS_WRITEBACK diff --git a/arch/xtensa/lib/usercopy.S b/arch/xtensa/lib/usercopy.S index ace1892a875e..7ea4dd68893e 100644 --- a/arch/xtensa/lib/usercopy.S +++ b/arch/xtensa/lib/usercopy.S @@ -222,8 +222,8 @@ __xtensa_copy_user: loopnez a7, .Loop2done #else /* !XCHAL_HAVE_LOOPS */ beqz a7, .Loop2done - slli a10, a7, 4 - add a10, a10, a3 # a10 = end of last 16B source chunk + slli a12, a7, 4 + add a12, a12, a3 # a12 = end of last 16B source chunk #endif /* !XCHAL_HAVE_LOOPS */ .Loop2: EX(l32i, a7, a3, 4, l_fixup) @@ -241,7 +241,7 @@ __xtensa_copy_user: EX(s32i, a9, a5, 12, s_fixup) addi a5, a5, 16 #if !XCHAL_HAVE_LOOPS - blt a3, a10, .Loop2 + blt a3, a12, .Loop2 #endif /* !XCHAL_HAVE_LOOPS */ .Loop2done: bbci.l a4, 3, .L12 diff --git a/arch/xtensa/platforms/iss/setup.c b/arch/xtensa/platforms/iss/setup.c index da7d18240866..391820539f0a 100644 --- a/arch/xtensa/platforms/iss/setup.c +++ b/arch/xtensa/platforms/iss/setup.c @@ -61,7 +61,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t" diff --git a/arch/xtensa/platforms/xt2000/setup.c b/arch/xtensa/platforms/xt2000/setup.c index b90555cb8089..87678961a8c8 100644 --- a/arch/xtensa/platforms/xt2000/setup.c +++ b/arch/xtensa/platforms/xt2000/setup.c @@ -72,7 +72,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t" diff --git a/arch/xtensa/platforms/xtfpga/setup.c b/arch/xtensa/platforms/xtfpga/setup.c index 57fd08b36f51..32c955e58e3d 100644 --- a/arch/xtensa/platforms/xtfpga/setup.c +++ b/arch/xtensa/platforms/xtfpga/setup.c @@ -63,7 +63,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t"