From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932616AbeD0JqX (ORCPT ); Fri, 27 Apr 2018 05:46:23 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:50262 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932515AbeD0JqR (ORCPT ); Fri, 27 Apr 2018 05:46:17 -0400 X-Google-Smtp-Source: AB8JxZo2oWrhxwGggfeX/aRdofPV/tPdehCXlOAdbh1kL9Np/BPEPzEH3HsLli4Uki+0pH+H2rWOxw== Subject: Re: [PATCH v2 2/2] soc: mediatek: add a fixed wait for SRAM stable To: Sean Wang Cc: rjw@rjwysocki.net, khilman@baylibre.com, ulf.hansson@linaro.org, linux-mediatek@lists.infradead.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Weiyi Lu References: <2e16481e1477dfae0cfb24568d8111da81d92628.1524472331.git.sean.wang@mediatek.com> <0ef8e87ba7156e626d1a1a48388f222ce917099b.1524472331.git.sean.wang@mediatek.com> <51840588-96e4-2520-f3d7-a61e74da6814@gmail.com> <1524476340.12322.14.camel@mtkswgap22> From: Matthias Brugger Openpgp: preference=signencrypt Autocrypt: addr=matthias.bgg@gmail.com; prefer-encrypt=mutual; keydata= xsFNBFP1zgUBEAC21D6hk7//0kOmsUrE3eZ55kjc9DmFPKIz6l4NggqwQjBNRHIMh04BbCMY fL3eT7ZsYV5nur7zctmJ+vbszoOASXUpfq8M+S5hU2w7sBaVk5rpH9yW8CUWz2+ZpQXPJcFa OhLZuSKB1F5JcvLbETRjNzNU7B3TdS2+zkgQQdEyt7Ij2HXGLJ2w+yG2GuR9/iyCJRf10Okq gTh//XESJZ8S6KlOWbLXRE+yfkKDXQx2Jr1XuVvM3zPqH5FMg8reRVFsQ+vI0b+OlyekT/Xe 0Hwvqkev95GG6x7yseJwI+2ydDH6M5O7fPKFW5mzAdDE2g/K9B4e2tYK6/rA7Fq4cqiAw1+u EgO44+eFgv082xtBez5WNkGn18vtw0LW3ESmKh19u6kEGoi0WZwslCNaGFrS4M7OH+aOJeqK fx5dIv2CEbxc6xnHY7dwkcHikTA4QdbdFeUSuj4YhIZ+0QlDVtS1QEXyvZbZky7ur9rHkZvP ZqlUsLJ2nOqsmahMTIQ8Mgx9SLEShWqD4kOF4zNfPJsgEMB49KbS2o9jxbGB+JKupjNddfxZ HlH1KF8QwCMZEYaTNogrVazuEJzx6JdRpR3sFda/0x5qjTadwIW6Cl9tkqe2h391dOGX1eOA 1ntn9O/39KqSrWNGvm+1raHK+Ev1yPtn0Wxn+0oy1tl67TxUjQARAQABzSlNYXR0aGlhcyBC cnVnZ2VyIDxtYXR0aGlhcy5iZ2dAZ21haWwuY29tPsLBkgQTAQIAPAIbAwYLCQgHAwIGFQgC CQoLBBYCAwECHgECF4AWIQTmuZIYwPLDJRwsOhfZFAuyVhMC8QUCWt3scQIZAQAKCRDZFAuy VhMC8WzRD/4onkC+gCxG+dvui5SXCJ7bGLCu0xVtiGC673Kz5Aq3heITsERHBV0BqqctOEBy ZozQQe2Hindu9lasOmwfH8+vfTK+2teCgWesoE3g3XKbrOCB4RSrQmXGC3JYx6rcvMlLV/Ch YMRR3qv04BOchnjkGtvm9aZWH52/6XfChyh7XYndTe5F2bqeTjt+kF/ql+xMc4E6pniqIfkv c0wsH4CkBHqoZl9w5e/b9MspTqsU9NszTEOFhy7p2CYw6JEa/vmzR6YDzGs8AihieIXDOfpT DUr0YUlDrwDSrlm/2MjNIPTmSGHH94ScOqu/XmGW/0q1iar/Yr0leomUOeeEzCqQtunqShtE 4Mn2uEixFL+9jiVtMjujr6mphznwpEqObPCZ3IcWqOFEz77rSL+oqFiEA03A2WBDlMm++Sve 9jpkJBLosJRhAYmQ6ey6MFO6Krylw1LXcq5z1XQQavtFRgZoruHZ3XlhT5wcfLJtAqrtfCe0 aQ0kJW+4zj9/So0uxJDAtGuOpDYnmK26dgFN0tAhVuNInEVhtErtLJHeJzFKJzNyQ4GlCaLw jKcwWcqDJcrx9R7LsCu4l2XpKiyxY6fO4O8DnSleVll9NPfAZFZvf8AIy3EQ8BokUsiuUYHz wUo6pclk55PZRaAsHDX/fNr24uC6Eh5oNQ+v4Pax/gtyyc7BTQRT9gkSARAApxtQ4zUMC512 kZ+gCiySFcIF/mAf7+l45689Tn7LI1xmPQrAYJDoqQVXcyh3utgtvBvDLmpQ+1BfEONDWc8K RP6Abo35YqBx3udAkLZgr/RmEg3+Tiof+e1PJ2zRh5zmdei5MT8biE2zVd9DYSJHZ8ltEWIA LC9lAsv9oa+2L6naC+KFF3i0m5mxklgFoSthswUnonqvclsjYaiVPoSldDrreCPzmRCUd8zn f//Z4BxtlTw3SulF8weKLJ+Hlpw8lwb3sUl6yPS6pL6UV45gyWMe677bVUtxLYOu+kiv2B/+ nrNRDs7B35y/J4t8dtK0S3M/7xtinPiYRmsnJdk+sdAe8TgGkEaooF57k1aczcJlUTBQvlYA Eg2NJnqaKg3SCJ4fEuT8rLjzuZmLkoHNumhH/mEbyKca82HvANu5C9clyQusJdU+MNRQLRmO Ad/wxGLJ0xmAye7Ozja86AIzbEmuNhNH9xNjwbwSJNZefV2SoZUv0+V9EfEVxTzraBNUZifq v6hernMQXGxs+lBjnyl624U8nnQWnA8PwJ2hI3DeQou1HypLFPeY9DfWv4xYdkyeOtGpueeB lqhtMoZ0kDw2C3vzj77nWwBgpgn1Vpf4hG/sW/CRR6tuIQWWTvUM3ACa1pgEsBvIEBiVvPxy AtL+L+Lh1Sni7w3HBk1EJvUAEQEAAcLBXwQYAQIACQUCU/YJEgIbDAAKCRDZFAuyVhMC8Qnd EACuN16mvivnWwLDdypvco5PF8w9yrfZDKW4ggf9TFVB9skzMNCuQc+tc+QM+ni2c4kKIdz2 jmcg6QytgqVum6V1OsNmpjADaQkVp5jL0tmg6/KA9Tvr07Kuv+Uo4tSrS/4djDjJnXHEp/tB +Fw7CArNtUtLlc8SuADCmMD+kBOVWktZyzkBkDfBXlTWl46T/8291lEspDWe5YW1ZAH/HdCR 1rQNZWjNCpB2Cic58CYMD1rSonCnbfUeyZYNNhNHZosl4dl7f+am87Q2x3pK0DLSoJRxWb7v ZB0uo9CzCSm3I++aYozF25xQoT+7zCx2cQi33jwvnJAK1o4VlNx36RfrxzBqc1uZGzJBCQu4 8UjmUSsTwWC3HpE/D9sM+xACs803lFUIZC5H62G059cCPAXKgsFpNMKmBAWweBkVJAisoQeX 50OP+/11ArV0cv+fOTfJj0/KwFXJaaYh3LUQNILLBNxkSrhCLl8dUg53IbHx4NfIAgqxLWGf XM8DY1aFdU79pac005PuhxCWkKTJz3gCmznnoat4GCnL5gy/m0Qk45l4PFqwWXVLo9AQg2Kp 3mlIFZ6fsEKIAN5hxlbNvNb9V2Zo5bFZjPWPFTxOteM0omUAS+QopwU0yPLLGJVf2iCmItHc UXI+r2JwH1CJjrHWeQEI2ucSKsNa8FllDmG/fQ== Message-ID: <0ec15c8a-ca90-26c3-1ea6-00bf0d48b62a@gmail.com> Date: Fri, 27 Apr 2018 11:46:14 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <1524476340.12322.14.camel@mtkswgap22> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sean, On 04/23/2018 11:39 AM, Sean Wang wrote: > On Mon, 2018-04-23 at 11:31 +0200, Matthias Brugger wrote: >> >> On 04/23/2018 10:36 AM, sean.wang@mediatek.com wrote: >>> From: Sean Wang >>> >>> MT7622_POWER_DOMAIN_WB doesn't send an ACK when its managed SRAM becomes >>> stable, which is not like the behavior the other power domains should >>> have. Therefore, it's necessary for such a power domain to have a fixed >>> and well-predefined duration to wait until its managed SRAM can be allowed >>> to access by all functions running on the top. >>> >>> v1 -> v2: >>> - use MTK_SCPD_FWAIT_SRAM flag as an indication requiring force waiting. >>> >>> Signed-off-by: Sean Wang >>> Cc: Matthias Brugger >>> Cc: Ulf Hansson >>> Cc: Weiyi Lu >>> --- >>> drivers/soc/mediatek/mtk-scpsys.c | 24 ++++++++++++++++++------ >>> 1 file changed, 18 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c >>> index b1b45e4..d4f1a63 100644 >>> --- a/drivers/soc/mediatek/mtk-scpsys.c >>> +++ b/drivers/soc/mediatek/mtk-scpsys.c >>> @@ -32,6 +32,7 @@ >>> #define MTK_POLL_TIMEOUT (jiffies_to_usecs(HZ)) >>> >>> #define MTK_SCPD_ACTIVE_WAKEUP BIT(0) >>> +#define MTK_SCPD_FWAIT_SRAM BIT(1) >>> #define MTK_SCPD_CAPS(_scpd, _x) ((_scpd)->data->caps & (_x)) >>> >>> #define SPM_VDE_PWR_CON 0x0210 >>> @@ -237,11 +238,22 @@ static int scpsys_power_on(struct generic_pm_domain *genpd) >>> val &= ~scpd->data->sram_pdn_bits; >>> writel(val, ctl_addr); >>> >>> - /* wait until SRAM_PDN_ACK all 0 */ >>> - ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == 0, >>> - MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); >>> - if (ret < 0) >>> - goto err_pwr_ack; >>> + /* Either wait until SRAM_PDN_ACK all 0 or have a force wait */ >>> + if (!MTK_SCPD_CAPS(scpd, MTK_SCPD_FWAIT_SRAM)) { After having another look on the patch, could you change the order of the if: So that we check for the existence of the MTK_SCPD_FWAIT_SRAM and sleep and in the else branch we to the readl_poll_timeout. I think in the future this will make the code easier to understand as you can easily oversee the '!' negation in the if. Regards, Matthias >>> + ret = readl_poll_timeout(ctl_addr, tmp, (tmp & pdn_ack) == 0, >>> + MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); >>> + if (ret < 0) >>> + goto err_pwr_ack; >>> + } else { >>> + /* >>> + * Currently, MTK_SCPD_FWAIT_SRAM is necessary only for >>> + * MT7622_POWER_DOMAIN_WB and thus just a trivial setup is >>> + * applied here. If there're more domains which need to force >>> + * waiting for its own pre-defined value, the duration should >>> + * be coded in the caps field. >>> + */ >> >> I would say, if necessary in the future we can add a switch statement here. >> Other then that the patches look good. If you are OK, I'll just delete the last >> sentence when applying the patch. >> > > yes, it's okay for me. > >> Regards, >> Matthias >> >>> + usleep_range(12000, 12100); >>> + }; >>> >>> if (scpd->data->bus_prot_mask) { >>> ret = mtk_infracfg_clear_bus_protection(scp->infracfg, >>> @@ -785,7 +797,7 @@ static const struct scp_domain_data scp_domain_data_mt7622[] = { >>> .sram_pdn_ack_bits = 0, >>> .clk_id = {CLK_NONE}, >>> .bus_prot_mask = MT7622_TOP_AXI_PROT_EN_WB, >>> - .caps = MTK_SCPD_ACTIVE_WAKEUP, >>> + .caps = MTK_SCPD_ACTIVE_WAKEUP | MTK_SCPD_FWAIT_SRAM, >>> }, >>> }; >>> >>> > >