From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="jee2wC3v" Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B19098; Tue, 5 Dec 2023 04:02:05 -0800 (PST) Received: from pendragon.ideasonboard.com (213-243-189-158.bb.dnainternet.fi [213.243.189.158]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 36EEE844; Tue, 5 Dec 2023 13:01:23 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1701777683; bh=bKZroPFsFtSdTPyHK0rJbVB9cPk+QtCuoUpKU4CunHg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jee2wC3vSvY6cG7oCEtuQCbYH28IrZRKNXyIbJavutI6wA80Gy2Sm6o6cjQULbx5a M0SsPcBZFREcK+ZkNDNh13v/h4DHlS4XNrw2Xmk4OrPT6yn5HMFlQOfh2UlN/sZEjD nL3LaJ+XqCd35cYQ5mZorCOUYhcIbi1aF10XcdWY= Date: Tue, 5 Dec 2023 14:02:10 +0200 From: Laurent Pinchart To: Adam Ford Cc: Tomi Valkeinen , Dafna Hirschfeld , Mauro Carvalho Chehab , Heiko Stuebner , Paul Elder , Alexander Stein , kieran.bingham@ideasonboard.com, umang.jain@ideasonboard.com, linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/4] media: rkisp1: Fix IRQ handling due to shared interrupts Message-ID: <20231205120210.GC17394@pendragon.ideasonboard.com> References: <20231205-rkisp-irq-fix-v1-0-f4045c74ba45@ideasonboard.com> <20231205-rkisp-irq-fix-v1-3-f4045c74ba45@ideasonboard.com> <20231205082016.GA17394@pendragon.ideasonboard.com> <9b28dcf7-c9a0-4d68-9197-cdcdd9f0393b@ideasonboard.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Tue, Dec 05, 2023 at 05:49:30AM -0600, Adam Ford wrote: > On Tue, Dec 5, 2023 at 2:27 AM Tomi Valkeinen wrote: > > On 05/12/2023 10:20, Laurent Pinchart wrote: > > > On Tue, Dec 05, 2023 at 10:09:34AM +0200, Tomi Valkeinen wrote: > > >> The driver requests the interrupts as IRQF_SHARED, so the interrupt > > >> handlers can be called at any time. If such a call happens while the ISP > > >> is powered down, the SoC will hang as the driver tries to access the > > >> ISP registers. > > > > > > Is IRQF_SHARED actually needed ? > > > > I don't have any answer to that, but it seems to have always been there. > > Dropping it would simplify the code, but we can only do that if we are > > sure all the platforms the ISP is used on or will be used on won't share > > the interrupt. > > I can't speak for the Rockchip, but from what I can see, the imx8mp > has multiple causes for Interrupt 74 and 75, but they all appear to > be ISP1 and ISP2 related. The ISP has multiple interrupt lines. In some SoCs, they're all wired to a single line of the IRQ controller (e.g. RK3399 and i.MX8MP), while other SoCs use separate interrupts (e.g. PX30). I have checked the PX30, RK3399 and i.MX8MP datasheets, and the ISP interrupts are not shared with any other peripheral. I think it's thus safe to drop IRQF_SHARED. > > >> Fix this by adding a new field, 'irqs_enabled', which is used to bail > > >> out from the interrupt handler when the ISP is not operational. > > >> > > >> Signed-off-by: Tomi Valkeinen > > >> --- > > >> .../media/platform/rockchip/rkisp1/rkisp1-capture.c | 3 +++ > > >> .../media/platform/rockchip/rkisp1/rkisp1-common.h | 2 ++ > > >> drivers/media/platform/rockchip/rkisp1/rkisp1-csi.c | 3 +++ > > >> drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c | 21 +++++++++++++++++++++ > > >> drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c | 3 +++ > > >> 5 files changed, 32 insertions(+) > > >> > > >> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c > > >> index b50b044d22af..e92067897f28 100644 > > >> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c > > >> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-capture.c > > >> @@ -779,6 +779,9 @@ irqreturn_t rkisp1_capture_isr(int irq, void *ctx) > > >> unsigned int i; > > >> u32 status; > > >> > > >> + if (!rkisp1->irqs_enabled) > > >> + return IRQ_NONE; > > >> + > > >> status = rkisp1_read(rkisp1, RKISP1_CIF_MI_MIS); > > >> if (!status) > > >> return IRQ_NONE; > > >> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-common.h b/drivers/media/platform/rockchip/rkisp1/rkisp1-common.h > > >> index ec28907d978e..7f97fdf6e24c 100644 > > >> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-common.h > > >> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-common.h > > >> @@ -465,6 +465,7 @@ struct rkisp1_debug { > > >> * @debug: debug params to be exposed on debugfs > > >> * @info: version-specific ISP information > > >> * @irqs: IRQ line numbers > > >> + * @irqs_enabled: the hardware is enabled and can cause interrupts > > >> */ > > >> struct rkisp1_device { > > >> void __iomem *base_addr; > > >> @@ -488,6 +489,7 @@ struct rkisp1_device { > > >> struct rkisp1_debug debug; > > >> const struct rkisp1_info *info; > > >> int irqs[RKISP1_NUM_IRQS]; > > >> + bool irqs_enabled; > > >> }; > > >> > > >> /* > > >> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-csi.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-csi.c > > >> index 47f4353a1784..f6b54654b435 100644 > > >> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-csi.c > > >> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-csi.c > > >> @@ -184,6 +184,9 @@ irqreturn_t rkisp1_csi_isr(int irq, void *ctx) > > >> struct rkisp1_device *rkisp1 = dev_get_drvdata(dev); > > >> u32 val, status; > > >> > > >> + if (!rkisp1->irqs_enabled) > > >> + return IRQ_NONE; > > >> + > > >> status = rkisp1_read(rkisp1, RKISP1_CIF_MIPI_MIS); > > >> if (!status) > > >> return IRQ_NONE; > > >> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c > > >> index 1d60f4b8bd09..fbe03f7864e3 100644 > > >> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c > > >> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c > > >> @@ -306,6 +306,23 @@ static int __maybe_unused rkisp1_runtime_suspend(struct device *dev) > > >> { > > >> struct rkisp1_device *rkisp1 = dev_get_drvdata(dev); > > >> > > >> + rkisp1->irqs_enabled = false; > > >> + /* Make sure the IRQ handler will see the above */ > > >> + mb(); > > >> + > > >> + /* > > >> + * Wait until any running IRQ handler has returned. The IRQ handler > > >> + * may get called even after this (as it's a shared interrupt line) > > >> + * but the 'irqs_enabled' flag will make the handler return immediately. > > >> + */ > > >> + for (unsigned int i = 0; i < RKISP1_NUM_IRQS; ++i) { > > >> + if (rkisp1->irqs[i] == -1) > > >> + continue; > > >> + > > >> + if (i == 0 || rkisp1->irqs[i - 1] != rkisp1->irqs[i]) > > >> + synchronize_irq(rkisp1->irqs[i]); > > >> + } > > >> + > > >> clk_bulk_disable_unprepare(rkisp1->clk_size, rkisp1->clks); > > >> return pinctrl_pm_select_sleep_state(dev); > > >> } > > >> @@ -322,6 +339,10 @@ static int __maybe_unused rkisp1_runtime_resume(struct device *dev) > > >> if (ret) > > >> return ret; > > >> > > >> + rkisp1->irqs_enabled = true; > > >> + /* Make sure the IRQ handler will see the above */ > > >> + mb(); > > >> + > > >> return 0; > > >> } > > >> > > >> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c > > >> index dafbfd230542..d6b8786661ad 100644 > > >> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c > > >> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c > > >> @@ -1082,6 +1082,9 @@ irqreturn_t rkisp1_isp_isr(int irq, void *ctx) > > >> struct rkisp1_device *rkisp1 = dev_get_drvdata(dev); > > >> u32 status, isp_err; > > >> > > >> + if (!rkisp1->irqs_enabled) > > >> + return IRQ_NONE; > > >> + > > >> status = rkisp1_read(rkisp1, RKISP1_CIF_ISP_MIS); > > >> if (!status) > > >> return IRQ_NONE; -- Regards, Laurent Pinchart