From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756895AbcIGJrx (ORCPT ); Wed, 7 Sep 2016 05:47:53 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:65369 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754006AbcIGJpk (ORCPT ); Wed, 7 Sep 2016 05:45:40 -0400 From: Matt Redfearn To: Ralf Baechle CC: , Matt Redfearn , Adam Buchbinder , Masahiro Yamada , Kees Cook , , Markos Chandras , Paul Burton Subject: [PATCH v2 04/12] MIPS: pm-cps: Update comments on barrier instructions Date: Wed, 7 Sep 2016 10:45:12 +0100 Message-ID: <1473241520-14917-5-git-send-email-matt.redfearn@imgtec.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1473241520-14917-1-git-send-email-matt.redfearn@imgtec.com> References: <1473241520-14917-1-git-send-email-matt.redfearn@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.150.130.83] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This code makes large use of barriers, which had quite vague descriptions. Update the comments to make the choice of barrier and reason for it more clear. Signed-off-by: Matt Redfearn Reviewed-by: Paul Burton --- Changes in v2: Update comments on barriers arch/mips/kernel/pm-cps.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/mips/kernel/pm-cps.c b/arch/mips/kernel/pm-cps.c index 2faa227a032e..7e8d4aa22233 100644 --- a/arch/mips/kernel/pm-cps.c +++ b/arch/mips/kernel/pm-cps.c @@ -315,7 +315,7 @@ static int __init cps_gen_flush_fsb(u32 **pp, struct uasm_label **pl, i * line_size * line_stride, t0); } - /* Completion barrier */ + /* Barrier ensuring previous cache invalidates are complete */ uasm_i_sync(pp, stype_memory); uasm_i_ehb(pp); @@ -414,7 +414,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) uasm_il_beqz(&p, &r, t2, lbl_incready); uasm_i_addiu(&p, t1, t1, 1); - /* Ordering barrier */ + /* Barrier ensuring all CPUs see the updated r_nc_count value */ uasm_i_sync(&p, stype_ordering); /* @@ -467,7 +467,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) cps_gen_cache_routine(&p, &l, &r, &cpu_data[cpu].dcache, Index_Writeback_Inv_D, lbl_flushdcache); - /* Completion barrier */ + /* Barrier ensuring previous cache invalidates are complete */ uasm_i_sync(&p, stype_memory); uasm_i_ehb(&p); @@ -480,7 +480,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) uasm_i_sw(&p, t0, 0, r_pcohctl); uasm_i_lw(&p, t0, 0, r_pcohctl); - /* Sync to ensure previous interventions are complete */ + /* Barrier to ensure write to coherence control is complete */ uasm_i_sync(&p, stype_intervention); uasm_i_ehb(&p); @@ -526,7 +526,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) goto gen_done; } - /* Completion barrier */ + /* Barrier to ensure write to CPC command is complete */ uasm_i_sync(&p, stype_memory); uasm_i_ehb(&p); } @@ -561,7 +561,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) uasm_i_sw(&p, t0, 0, r_pcohctl); uasm_i_lw(&p, t0, 0, r_pcohctl); - /* Completion barrier */ + /* Barrier to ensure write to coherence control is complete */ uasm_i_sync(&p, stype_memory); uasm_i_ehb(&p); @@ -575,7 +575,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) uasm_il_beqz(&p, &r, t2, lbl_decready); uasm_i_andi(&p, v0, t1, (1 << fls(smp_num_siblings)) - 1); - /* Ordering barrier */ + /* Barrier ensuring all CPUs see the updated r_nc_count value */ uasm_i_sync(&p, stype_ordering); } @@ -597,7 +597,7 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) */ uasm_build_label(&l, p, lbl_secondary_cont); - /* Ordering barrier */ + /* Barrier ensuring all CPUs see the updated r_nc_count value */ uasm_i_sync(&p, stype_ordering); } -- 2.7.4