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Thu, 21 May 2020 12:00:14 -0400 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21438C061A0F for ; Thu, 21 May 2020 09:00:14 -0700 (PDT) Received: by mail-pg1-x542.google.com with SMTP id n11so3357461pgl.9 for ; Thu, 21 May 2020 09:00:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=jHirFrfUhrscDiyY19yFy1eojdIlJFYNDT0L5VP6NdE=; b=iyB4ngXROy5qTSwcL5Cvl5LAnn2U16sn3BZvQyGAClC2S6/xy2nQLtKiG2/8kwRklF WNVdSOimsudJuNLU7K5eiIGS5eRF8urxcHf9Ijf9Y2FlUwywDIWA9biynBY3D08eqBC4 kFPQ845JNwI3HI41jDcvAJEOoi1G3+mRda/sQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=jHirFrfUhrscDiyY19yFy1eojdIlJFYNDT0L5VP6NdE=; 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charset=utf-8 Content-Disposition: inline In-Reply-To: <1590049764-20912-3-git-send-email-akashast@codeaurora.org> Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Hi Akash, On Thu, May 21, 2020 at 01:59:19PM +0530, Akash Asthana wrote: > QUP core clock is shared among all the SE drivers present on particular > QUP wrapper, the system will reset(unclocked access) if earlycon used after > QUP core clock is put to 0 from other SE drivers before real console comes > up. > > As earlycon can't vote for it's QUP core need, to fix this add ICC > support to common/QUP wrapper driver and put vote for QUP core from > probe on behalf of earlycon and remove vote during earlycon exit call. > > Signed-off-by: Akash Asthana > Reported-by: Matthias Kaehlcke > --- > Change in V3: > - Add geni_remove_earlycon_icc_vote API that will be used by earlycon > exit function to remove ICC vote for earlyconsole. > - Remove suspend/resume hook for geni-se driver as we are no longer > removing earlyconsole ICC vote from system suspend, we are removing > from earlycon exit. > > Change in V4: > - As per Matthias comment make 'earlycon_wrapper' as static structure. > > Changes in V5: > - Vote for core path only after checking whether "qcom_geni" earlycon is > actually present or not by traversing over structure "console_drivers". > > Changes in V6: > - As per Matthias's comment removed NULL check for console_drivers global > struct, added NULL check for earlycon_wrapper in _remove_earlycon_icc_vote > API > - Addressed nitpicks from Andy. > > drivers/soc/qcom/qcom-geni-se.c | 68 +++++++++++++++++++++++++++++++++++ > drivers/tty/serial/qcom_geni_serial.c | 7 ++++ > include/linux/qcom-geni-se.h | 2 ++ > 3 files changed, 77 insertions(+) > > diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c > index 0b2526d..ac16bb1 100644 > --- a/drivers/soc/qcom/qcom-geni-se.c > +++ b/drivers/soc/qcom/qcom-geni-se.c > @@ -3,6 +3,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -90,11 +91,14 @@ struct geni_wrapper { > struct device *dev; > void __iomem *base; > struct clk_bulk_data ahb_clks[NUM_AHB_CLKS]; > + struct geni_icc_path to_core; > }; > > static const char * const icc_path_names[] = {"qup-core", "qup-config", > "qup-memory"}; > > +static struct geni_wrapper *earlycon_wrapper; > + > #define QUP_HW_VER_REG 0x4 > > /* Common SE registers */ > @@ -812,11 +816,38 @@ int geni_icc_disable(struct geni_se *se) > } > EXPORT_SYMBOL(geni_icc_disable); > > +void geni_remove_earlycon_icc_vote(void) > +{ > + struct geni_wrapper *wrapper; > + struct device_node *parent; > + struct device_node *child; > + > + if (!earlycon_wrapper) > + return; > + > + wrapper = earlycon_wrapper; > + parent = of_get_next_parent(wrapper->dev->of_node); > + for_each_child_of_node(parent, child) { > + if (!of_device_is_compatible(child, "qcom,geni-se-qup")) > + continue; > + wrapper = platform_get_drvdata(of_find_device_by_node(child)); > + icc_put(wrapper->to_core.path); > + wrapper->to_core.path = NULL; > + > + } > + of_node_put(parent); > + > + earlycon_wrapper = NULL; > +} > +EXPORT_SYMBOL(geni_remove_earlycon_icc_vote); > + > static int geni_se_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > struct resource *res; > struct geni_wrapper *wrapper; > + struct console __maybe_unused *bcon; > + bool __maybe_unused has_earlycon = false; > int ret; > > wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL); > @@ -839,6 +870,43 @@ static int geni_se_probe(struct platform_device *pdev) > } > } > > +#ifdef CONFIG_SERIAL_EARLYCON > + for_each_console(bcon) { > + if (!strcmp(bcon->name, "qcom_geni")) { > + has_earlycon = true; > + break; > + } > + } > + if (!has_earlycon) > + goto exit; > + > + wrapper->to_core.path = devm_of_icc_get(dev, "qup-core"); > + if (IS_ERR(wrapper->to_core.path)) > + return PTR_ERR(wrapper->to_core.path); > + /* > + * Put minmal BW request on core clocks on behalf of early console. > + * The vote will be removed earlycon exit function. > + * > + * Note: We are putting vote on each QUP wrapper instead only to which > + * earlycon is connected because QUP core clock of different wrapper > + * share same voltage domain. If core1 is put to 0, then core2 will > + * also run at 0, if not voted. Default ICC vote will be removed ASA > + * we touch any of the core clock. > + * core1 = core2 = max(core1, core2) > + */ > + ret = icc_set_bw(wrapper->to_core.path, GENI_DEFAULT_BW, > + GENI_DEFAULT_BW); > + if (ret) { > + dev_err(&pdev->dev, "%s: ICC BW voting failed for core :%d\n", nit: " ... core: %d\n". Reviewed-by: Matthias Kaehlcke