From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932071AbcF3CCR (ORCPT ); Wed, 29 Jun 2016 22:02:17 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:40461 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751840AbcF3CB0 (ORCPT ); Wed, 29 Jun 2016 22:01:26 -0400 From: Chaotian Jing To: Ulf Hansson CC: Matthias Brugger , Chaotian Jing , Nicolas Boichat , Douglas Anderson , Geert Uytterhoeven , , , , , , Sascha Hauer , Daniel Kurtz , Wei-Ning Huang Subject: [PATCH 4/4] mmc: mediatek: perfer to use rise edge latching Date: Thu, 30 Jun 2016 10:01:01 +0800 Message-ID: <1467252061-3791-5-git-send-email-chaotian.jing@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty In-Reply-To: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> References: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org in our host design, rise edge latching is more stable than fall edge latching. so that if rise edge has enough margin, no need scan fall edge. Signed-off-by: Chaotian Jing --- drivers/mmc/host/mtk-sd.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 91277b9..84e9afc 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -1328,7 +1328,7 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int cmd_err; int i; @@ -1341,6 +1341,11 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); for (i = 0; i < PAD_DELAY_MAX; i++) { @@ -1350,10 +1355,9 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); @@ -1374,7 +1378,7 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int i, ret; @@ -1387,6 +1391,11 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); @@ -1397,14 +1406,10 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); - /* Rising edge is more stable, prefer to use it */ - if (final_rise_delay.maxlen >= 10) - final_maxlen = final_rise_delay.maxlen; if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); -- 1.8.1.1.dirty From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chaotian Jing Subject: [PATCH 4/4] mmc: mediatek: perfer to use rise edge latching Date: Thu, 30 Jun 2016 10:01:01 +0800 Message-ID: <1467252061-3791-5-git-send-email-chaotian.jing@mediatek.com> References: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: Matthias Brugger , Chaotian Jing , Nicolas Boichat , Douglas Anderson , Geert Uytterhoeven , linux-mmc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, srv_heupstream@mediatek.com, Sascha Hauer , Daniel Kurtz , Wei-Ning Huang List-Id: linux-mmc@vger.kernel.org in our host design, rise edge latching is more stable than fall edge latching. so that if rise edge has enough margin, no need scan fall edge. Signed-off-by: Chaotian Jing --- drivers/mmc/host/mtk-sd.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 91277b9..84e9afc 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -1328,7 +1328,7 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int cmd_err; int i; @@ -1341,6 +1341,11 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); for (i = 0; i < PAD_DELAY_MAX; i++) { @@ -1350,10 +1355,9 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); @@ -1374,7 +1378,7 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int i, ret; @@ -1387,6 +1391,11 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); @@ -1397,14 +1406,10 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); - /* Rising edge is more stable, prefer to use it */ - if (final_rise_delay.maxlen >= 10) - final_maxlen = final_rise_delay.maxlen; if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); -- 1.8.1.1.dirty From mboxrd@z Thu Jan 1 00:00:00 1970 From: chaotian.jing@mediatek.com (Chaotian Jing) Date: Thu, 30 Jun 2016 10:01:01 +0800 Subject: [PATCH 4/4] mmc: mediatek: perfer to use rise edge latching In-Reply-To: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> References: <1467252061-3791-1-git-send-email-chaotian.jing@mediatek.com> Message-ID: <1467252061-3791-5-git-send-email-chaotian.jing@mediatek.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org in our host design, rise edge latching is more stable than fall edge latching. so that if rise edge has enough margin, no need scan fall edge. Signed-off-by: Chaotian Jing --- drivers/mmc/host/mtk-sd.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 91277b9..84e9afc 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -1328,7 +1328,7 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int cmd_err; int i; @@ -1341,6 +1341,11 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); for (i = 0; i < PAD_DELAY_MAX; i++) { @@ -1350,10 +1355,9 @@ static int msdc_tune_response(struct mmc_host *mmc, u32 opcode) if (!cmd_err) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_RSPL); @@ -1374,7 +1378,7 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) { struct msdc_host *host = mmc_priv(mmc); u32 rise_delay = 0, fall_delay = 0; - struct msdc_delay_phase final_rise_delay, final_fall_delay; + struct msdc_delay_phase final_rise_delay, final_fall_delay = { 0,}; u8 final_delay, final_maxlen; int i, ret; @@ -1387,6 +1391,11 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) rise_delay |= (1 << i); } + final_rise_delay = get_best_delay(host, rise_delay); + /* if rising edge has enough margin, then do not scan falling edge */ + if (final_rise_delay.maxlen >= 10 || + (final_rise_delay.start == 0 && final_rise_delay.maxlen >= 4)) + goto skip_fall; sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_set_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); @@ -1397,14 +1406,10 @@ static int msdc_tune_data(struct mmc_host *mmc, u32 opcode) if (!ret) fall_delay |= (1 << i); } - - final_rise_delay = get_best_delay(host, rise_delay); final_fall_delay = get_best_delay(host, fall_delay); +skip_fall: final_maxlen = max(final_rise_delay.maxlen, final_fall_delay.maxlen); - /* Rising edge is more stable, prefer to use it */ - if (final_rise_delay.maxlen >= 10) - final_maxlen = final_rise_delay.maxlen; if (final_maxlen == final_rise_delay.maxlen) { sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_DSPL); sdr_clr_bits(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL); -- 1.8.1.1.dirty