From patchwork Tue Jul 14 15:04:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 1328945 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=cQSVL88A; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B5kMR0xCpz9sRN for ; Wed, 15 Jul 2020 01:04:51 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726384AbgGNPEt (ORCPT ); Tue, 14 Jul 2020 11:04:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59450 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727848AbgGNPEs (ORCPT ); Tue, 14 Jul 2020 11:04:48 -0400 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DC3EC08C5C1 for ; Tue, 14 Jul 2020 08:04:48 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id k4so7122932pld.12 for ; Tue, 14 Jul 2020 08:04:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=69EodTdWYHlEAq5QPFBw8533OrGBXqn7j8SYE13YOZs=; b=cQSVL88ANjkwN4gGvrPeJaPo6cD8kadt+RcL4kRtj568HiFgABjsmINlN7cj7LpxME 7cl3m4SHsKCc3FSaiHNy+jsW+xKTCF//O4QSQujOITFjxZNfj7URCPQ20mjS97UyRgCD 2yayid8YdwA9tPHqqkEh3DRab59yP6eJjxYLw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=69EodTdWYHlEAq5QPFBw8533OrGBXqn7j8SYE13YOZs=; b=k9PQy9wzTXAGbiYzE3jeVEZH8V7fqbGLcTxT+G72VSu+p2DQfnvnbrLlJ8RXNBc2BK 9v+lzo2p1A05028Cfe54B08QwtNwUG6yFD/NLNTmFuekOoqOzi3DuLvk4IxrCPnAY65Y xo+OoofcUh/RX4l0KNPvUpTEAQ3hIrP2FX4afPsrYtj09gmgG4miqksY4Io8Clpdg2F9 DLDiITHaODkKSNoqv747Id+ms/vKWE3x+dtdm6CiCYLlrtwSZNLzVeH6I3QlSb+2eXG4 dp1N2rtfFzxw9t1JLqdBReVi56daBRG5X54vMrFQ6eZu1WF3E1OJmPG6RUgo5ylIa2u6 L1ew== X-Gm-Message-State: AOAM533nXXkOQ5aSsJP9V0ZjmJCK8G5q+2akNX8OQHKv50jZU6rHq5EP CoKELyL1TIx2Oeygv82RWmLRRA== X-Google-Smtp-Source: ABdhPJwiBC+kV8XEGEiCll0NbA71iPHEzbM0ilNZUq825EkI66xmzeU4QYutwOVwCVoe6Yi5pK69YA== X-Received: by 2002:a17:902:6b0c:: with SMTP id o12mr4353185plk.321.1594739087887; Tue, 14 Jul 2020 08:04:47 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:42b0:34ff:fe3d:58e6]) by smtp.gmail.com with ESMTPSA id n18sm18849700pfd.99.2020.07.14.08.04.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jul 2020 08:04:47 -0700 (PDT) From: Douglas Anderson To: linus.walleij@linaro.org Cc: rnayak@codeaurora.org, mkshah@codeaurora.org, Marc Zyngier , ilina@codeaurora.org, cychiang@chromium.org, swboyd@chromium.org, bjorn.andersson@linaro.org, agross@kernel.org, linux-arm-msm@vger.kernel.org, Douglas Anderson , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] pinctrl: qcom: Handle broken/missing PDC dual edge IRQs on sc7180 Date: Tue, 14 Jul 2020 08:04:17 -0700 Message-Id: <20200714080254.v3.1.Ie0d730120b232a86a4eac1e2909bcbec844d1766@changeid> X-Mailer: git-send-email 2.27.0.389.gc38d7665816-goog MIME-Version: 1.0 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Depending on how you look at it, you can either say that: a) There is a PDC hardware issue (with the specific IP rev that exists on sc7180) that causes the PDC not to work properly when configured to handle dual edges. b) The dual edge feature of the PDC hardware was only added in later HW revisions and thus isn't in all hardware. Regardless of how you look at it, let's work around the lack of dual edge support by only ever letting our parent see requests for single edge interrupts on affected hardware. NOTE: it's possible that a driver requesting a dual edge interrupt might get several edges coalesced into a single IRQ. For instance if a line starts low and then goes high and low again, the driver that requested the IRQ is not guaranteed to be called twice. However, it is guaranteed that once the driver's interrupt handler starts running its first instruction that any new edges coming in will cause the interrupt to fire again. This is relatively commonplace for dual-edge gpio interrupts (many gpio controllers require software to emulate dual edge with single edge) so client drivers should be setup to handle it. Fixes: e35a6ae0eb3a ("pinctrl/msm: Setup GPIO chip in hierarchy") Signed-off-by: Douglas Anderson Reviewed-by: Marc Zyngier --- As far as I can tell everything here should work and the limited testing I'm able to give it shows that, in fact, I can detect both edges. I specifically left off Reviewed-by and Tested-by tags from v2 becuase I felt that the implementation had changed just enough to invalidate previous reviews / testing. Hopefully it's not too much of a hassle for folks to re-review and re-test. Changes in v3: - Rate limit the warning. Changes in v2: - Use handle_fasteoi_ack_irq() and switch edges in the Ack now. - If we change types, switch back to the normal handle_fasteoi_irq(). - No extra locking. - Properly print an error if we hit 100 loops w/ no stability. - Beefed up the commit message. drivers/pinctrl/qcom/Kconfig | 2 + drivers/pinctrl/qcom/pinctrl-msm.c | 74 ++++++++++++++++++++++++++- drivers/pinctrl/qcom/pinctrl-msm.h | 4 ++ drivers/pinctrl/qcom/pinctrl-sc7180.c | 1 + 4 files changed, 79 insertions(+), 2 deletions(-) diff --git a/drivers/pinctrl/qcom/Kconfig b/drivers/pinctrl/qcom/Kconfig index ff1ee159dca2..f8ff30cdafa6 100644 --- a/drivers/pinctrl/qcom/Kconfig +++ b/drivers/pinctrl/qcom/Kconfig @@ -7,6 +7,8 @@ config PINCTRL_MSM select PINCONF select GENERIC_PINCONF select GPIOLIB_IRQCHIP + select IRQ_DOMAIN_HIERARCHY + select IRQ_FASTEOI_HIERARCHY_HANDLERS config PINCTRL_APQ8064 tristate "Qualcomm APQ8064 pin controller driver" diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c index 83b7d64bc4c1..c322f30a2064 100644 --- a/drivers/pinctrl/qcom/pinctrl-msm.c +++ b/drivers/pinctrl/qcom/pinctrl-msm.c @@ -832,6 +832,52 @@ static void msm_gpio_irq_unmask(struct irq_data *d) msm_gpio_irq_clear_unmask(d, false); } +/** + * msm_gpio_update_dual_edge_parent() - Prime next edge for IRQs handled by parent. + * @d: The irq dta. + * + * This is much like msm_gpio_update_dual_edge_pos() but for IRQs that are + * normally handled by the parent irqchip. The logic here is slightly + * different due to what's easy to do with our parent, but in principle it's + * the same. + */ +static void msm_gpio_update_dual_edge_parent(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct msm_pinctrl *pctrl = gpiochip_get_data(gc); + const struct msm_pingroup *g = &pctrl->soc->groups[d->hwirq]; + int loop_limit = 100; + unsigned int val; + unsigned int type; + + /* Read the value and make a guess about what edge we need to catch */ + val = msm_readl_io(pctrl, g) & BIT(g->in_bit); + type = val ? IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING; + + do { + /* Set the parent to catch the next edge */ + irq_chip_set_type_parent(d, type); + + /* + * Possibly the line changed between when we last read "val" + * (and decided what edge we needed) and when set the edge. + * If the value didn't change (or changed and then changed + * back) then we're done. + */ + val = msm_readl_io(pctrl, g) & BIT(g->in_bit); + if (type == IRQ_TYPE_EDGE_RISING) { + if (!val) + return; + type = IRQ_TYPE_EDGE_FALLING; + } else if (type == IRQ_TYPE_EDGE_FALLING) { + if (val) + return; + type = IRQ_TYPE_EDGE_RISING; + } + } while (loop_limit-- > 0); + dev_warn_once(pctrl->dev, "dual-edge irq failed to stabilize\n"); +} + static void msm_gpio_irq_ack(struct irq_data *d) { struct gpio_chip *gc = irq_data_get_irq_chip_data(d); @@ -840,8 +886,11 @@ static void msm_gpio_irq_ack(struct irq_data *d) unsigned long flags; u32 val; - if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) + if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) { + if (test_bit(d->hwirq, pctrl->dual_edge_irqs)) + msm_gpio_update_dual_edge_parent(d); return; + } g = &pctrl->soc->groups[d->hwirq]; @@ -860,6 +909,17 @@ static void msm_gpio_irq_ack(struct irq_data *d) raw_spin_unlock_irqrestore(&pctrl->lock, flags); } +static bool msm_gpio_needs_dual_edge_parent_workaround(struct irq_data *d, + unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct msm_pinctrl *pctrl = gpiochip_get_data(gc); + + return type == IRQ_TYPE_EDGE_BOTH && + pctrl->soc->wakeirq_dual_edge_errata && d->parent_data && + test_bit(d->hwirq, pctrl->skip_wake_irqs); +} + static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type) { struct gpio_chip *gc = irq_data_get_irq_chip_data(d); @@ -868,11 +928,21 @@ static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type) unsigned long flags; u32 val; + if (msm_gpio_needs_dual_edge_parent_workaround(d, type)) { + set_bit(d->hwirq, pctrl->dual_edge_irqs); + irq_set_handler_locked(d, handle_fasteoi_ack_irq); + msm_gpio_update_dual_edge_parent(d); + return 0; + } + if (d->parent_data) irq_chip_set_type_parent(d, type); - if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) + if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) { + clear_bit(d->hwirq, pctrl->dual_edge_irqs); + irq_set_handler_locked(d, handle_fasteoi_irq); return 0; + } g = &pctrl->soc->groups[d->hwirq]; diff --git a/drivers/pinctrl/qcom/pinctrl-msm.h b/drivers/pinctrl/qcom/pinctrl-msm.h index 9452da18a78b..7486fe08eb9b 100644 --- a/drivers/pinctrl/qcom/pinctrl-msm.h +++ b/drivers/pinctrl/qcom/pinctrl-msm.h @@ -113,6 +113,9 @@ struct msm_gpio_wakeirq_map { * @pull_no_keeper: The SoC does not support keeper bias. * @wakeirq_map: The map of wakeup capable GPIOs and the pin at PDC/MPM * @nwakeirq_map: The number of entries in @wakeirq_map + * @wakeirq_dual_edge_errata: If true then GPIOs using the wakeirq_map need + * to be aware that their parent can't handle dual + * edge interrupts. */ struct msm_pinctrl_soc_data { const struct pinctrl_pin_desc *pins; @@ -128,6 +131,7 @@ struct msm_pinctrl_soc_data { const int *reserved_gpios; const struct msm_gpio_wakeirq_map *wakeirq_map; unsigned int nwakeirq_map; + bool wakeirq_dual_edge_errata; }; extern const struct dev_pm_ops msm_pinctrl_dev_pm_ops; diff --git a/drivers/pinctrl/qcom/pinctrl-sc7180.c b/drivers/pinctrl/qcom/pinctrl-sc7180.c index 1b6465a882f2..1d9acad3c1ce 100644 --- a/drivers/pinctrl/qcom/pinctrl-sc7180.c +++ b/drivers/pinctrl/qcom/pinctrl-sc7180.c @@ -1147,6 +1147,7 @@ static const struct msm_pinctrl_soc_data sc7180_pinctrl = { .ntiles = ARRAY_SIZE(sc7180_tiles), .wakeirq_map = sc7180_pdc_map, .nwakeirq_map = ARRAY_SIZE(sc7180_pdc_map), + .wakeirq_dual_edge_errata = true, }; static int sc7180_pinctrl_probe(struct platform_device *pdev)