From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8CFF726AFF; Thu, 5 Dec 2024 10:25:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733394316; cv=none; b=gE3dvKfpjSqWE8rox0pDUgsZeBcnSuwn+33bD+2S1y7LsTcz2TO0R86pcGDs0nYc+uESSzyc5pwOR3YN6EMDWAJ8WLIoHbQLNxe/8lg2WbBdI3cb80feMoZRKLPh2K+2N8lW7c+ye7hfyk9wYvTvR+LAC+zmG/LERpSSqRQQdkM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733394316; c=relaxed/simple; bh=ZJ4S4rNEnh/7WF34+Cs6LWN0Zkt6lyhksJC0cFFlqIQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PloV12F2ZUDR9nui4kvfUOB2I9Rbb8pc0os5KpKhgOHjdQxNz0+1JyXEsHxvoe0uChwhdI2KlbURaZj0Rx5pBEYuGef7Fdd2VDKkNGs+B5rkWUQSjLStDxbNkQI8yTT9YppcXabqrf3UoxK0soctPDRs3iLSiYJIqWRxTm8uijQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dvqVQHE9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dvqVQHE9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22B3DC4CED1; Thu, 5 Dec 2024 10:25:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733394316; bh=ZJ4S4rNEnh/7WF34+Cs6LWN0Zkt6lyhksJC0cFFlqIQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dvqVQHE9jp7pk+jU9f+CQgDHRpTrZltyTe2qQIEqiJYJUNF3Q0dWjog+pjeeyAiy/ 8s47hPCgmt9rI4fgwqYPw4048P7C3ISV80w/Q3OjWwqYDs4uKHlJC5X8/3t8Ymb3EK jrEnvQVaX7VrB9Szmz1sqnKvXd55AI8piYeLZCIUtEjPAqKX88bSH7m3hwXXsfK+yN k7Jzx2psRCGDbKKvDAJe+Ob+xIqwAKDpgCXQKXqXROtAHYP6WaPTv83fr/9l5rofe+ vwNskYI+POPWTT0o6UVBJLlMWb4rWmeXoUFDWiDl3jdYmIdzJ8VTA4KKZGvX6zjqzs 21fCnttBFHqBA== Date: Thu, 5 Dec 2024 11:25:07 +0100 From: Lorenzo Pieralisi To: Frank Li Cc: Bjorn Helgaas , Richard Zhu , Lucas Stach , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, imx@lists.linux.dev, alyssa@rosenzweig.io, bpf@vger.kernel.org, broonie@kernel.org, jgg@ziepe.ca, joro@8bytes.org, lgirdwood@gmail.com, maz@kernel.org, p.zabel@pengutronix.de, robin.murphy@arm.com, will@kernel.org Subject: Re: [PATCH v7 2/2] PCI: imx6: Add IOMMU and ITS MSI support for i.MX95 Message-ID: References: <20241203-imx95_lut-v7-0-d0cd6293225e@nxp.com> <20241203-imx95_lut-v7-2-d0cd6293225e@nxp.com> Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241203-imx95_lut-v7-2-d0cd6293225e@nxp.com> On Tue, Dec 03, 2024 at 06:27:16PM -0500, Frank Li wrote: > For the i.MX95, configuration of a LUT is necessary to convert Bus Device > Function (BDF) to stream IDs, which are utilized by both IOMMU and ITS. > This involves examining the msi-map and smmu-map to ensure consistent This involves checking msi-map and iommu-map device tree properties to... > mapping of PCI BDF to the same stream IDs. Subsequently, LUT-related > registers are configured. In the absence of an msi-map, the built-in MSI > controller is utilized as a fallback. > > Register a PCI bus callback function to handle enable_device() and > disable_device() operations, setting up the LUT whenever a new PCI device > is enabled. > > Acked-by: Richard Zhu > Signed-off-by: Frank Li > --- > Change from v5 to v6 > - change comment rid to RID > - some mini change according to mani's feedback > > Change from v4 to v5 > - rework commt message > - add comment for mutex > - s/reqid/rid/ > - keep only one loop when enable lut > - add warning when try to add duplicate rid > - Replace hardcode 0xffff with IMX95_PE0_LUT_MASK > - Fix some error message > > Change from v3 to v4 > - Check target value at of_map_id(). > - of_node_put() for target. > - add case for msi-map exist, but rid entry is not exist. > > Change from v2 to v3 > - Use the "target" argument of of_map_id() > - Check if rid already in lut table when enable device > > change from v1 to v2 > - set callback to pci_host_bridge instead pci->ops. > --- > drivers/pci/controller/dwc/pci-imx6.c | 183 +++++++++++++++++++++++++++++++++- > 1 file changed, 182 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index c8d5c90aa4d45..ac5caa7b05075 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -55,6 +55,22 @@ > #define IMX95_PE0_GEN_CTRL_3 0x1058 > #define IMX95_PCIE_LTSSM_EN BIT(0) > > +#define IMX95_PE0_LUT_ACSCTRL 0x1008 > +#define IMX95_PEO_LUT_RWA BIT(16) > +#define IMX95_PE0_LUT_ENLOC GENMASK(4, 0) > + > +#define IMX95_PE0_LUT_DATA1 0x100c > +#define IMX95_PE0_LUT_VLD BIT(31) > +#define IMX95_PE0_LUT_DAC_ID GENMASK(10, 8) > +#define IMX95_PE0_LUT_STREAM_ID GENMASK(5, 0) > + > +#define IMX95_PE0_LUT_DATA2 0x1010 > +#define IMX95_PE0_LUT_REQID GENMASK(31, 16) > +#define IMX95_PE0_LUT_MASK GENMASK(15, 0) > + > +#define IMX95_SID_MASK GENMASK(5, 0) > +#define IMX95_MAX_LUT 32 > + > #define to_imx_pcie(x) dev_get_drvdata((x)->dev) > > enum imx_pcie_variants { > @@ -87,6 +103,7 @@ enum imx_pcie_variants { > * workaround suspend resume on some devices which are affected by this errata. > */ > #define IMX_PCIE_FLAG_BROKEN_SUSPEND BIT(9) > +#define IMX_PCIE_FLAG_HAS_LUT BIT(10) > > #define imx_check_flag(pci, val) (pci->drvdata->flags & val) > > @@ -139,6 +156,9 @@ struct imx_pcie { > struct device *pd_pcie_phy; > struct phy *phy; > const struct imx_pcie_drvdata *drvdata; > + > + /* Ensure that only one device's LUT is configured at any given time */ > + struct mutex lock; > }; > > /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ > @@ -930,6 +950,159 @@ static void imx_pcie_stop_link(struct dw_pcie *pci) > imx_pcie_ltssm_disable(dev); > } > > +static int imx_pcie_add_lut(struct imx_pcie *imx_pcie, u16 rid, u8 sid) > +{ > + struct dw_pcie *pci = imx_pcie->pci; > + struct device *dev = pci->dev; > + u32 data1, data2; > + int free = -1; > + int i; > + > + if (sid >= 64) { > + dev_err(dev, "Invalid SID for index %d\n", sid); > + return -EINVAL; > + } > + > + guard(mutex)(&imx_pcie->lock); > + > + /* > + * Iterate through all LUT entries to check for duplicate RID and > + * identify the first available entry. Configure this available entry > + * immediately after verification to avoid rescanning it. > + */ > + for (i = 0; i < IMX95_MAX_LUT; i++) { > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_ACSCTRL, IMX95_PEO_LUT_RWA | i); > + regmap_read(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA1, &data1); > + > + if (!(data1 & IMX95_PE0_LUT_VLD)) { > + if (free < 0) > + free = i; > + continue; > + } > + > + regmap_read(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, &data2); > + > + /* Do not add duplicate RID */ > + if (rid == FIELD_GET(IMX95_PE0_LUT_REQID, data2)) { > + dev_warn(dev, "Existing LUT entry available for RID (%d)", rid); > + return 0; > + } > + } > + > + if (free < 0) { > + dev_err(dev, "LUT entry is not available\n"); > + return -ENOSPC; > + } > + > + data1 = FIELD_PREP(IMX95_PE0_LUT_DAC_ID, 0); > + data1 |= FIELD_PREP(IMX95_PE0_LUT_STREAM_ID, sid); > + data1 |= IMX95_PE0_LUT_VLD; > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA1, data1); > + > + data2 = IMX95_PE0_LUT_MASK; /* Match all bits of RID */ > + data2 |= FIELD_PREP(IMX95_PE0_LUT_REQID, rid); > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, data2); > + > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_ACSCTRL, free); > + > + return 0; > +} > + > +static void imx_pcie_remove_lut(struct imx_pcie *imx_pcie, u16 rid) > +{ > + u32 data2; > + int i; > + > + guard(mutex)(&imx_pcie->lock); > + > + for (i = 0; i < IMX95_MAX_LUT; i++) { > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_ACSCTRL, IMX95_PEO_LUT_RWA | i); > + regmap_read(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, &data2); > + if (FIELD_GET(IMX95_PE0_LUT_REQID, data2) == rid) { > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA1, 0); > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, 0); > + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_ACSCTRL, i); > + > + break; > + } > + } > +} > + > +static int imx_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_dev *pdev) > +{ > + struct imx_pcie *imx_pcie = to_imx_pcie(to_dw_pcie_from_pp(bridge->sysdata)); > + u32 sid_i, sid_m, rid = pci_dev_id(pdev); > + struct device_node *target; > + struct device *dev; > + int err_i, err_m; > + > + dev = imx_pcie->pci->dev; > + > + target = NULL; > + err_i = of_map_id(dev->of_node, rid, "iommu-map", "iommu-map-mask", &target, &sid_i); > + if (target) > + of_node_put(target); > + else > + err_i = -EINVAL; Why ? If target == NULL err_i is already set to a negative value ? > + > + target = NULL; > + err_m = of_map_id(dev->of_node, rid, "msi-map", "msi-map-mask", &target, &sid_m); > + > + /* > + * Return failure if msi-map exist and no entry for RID because dwc common > + * driver will skip setting up built-in MSI controller if msi-map existed. This is not ideal - to depend on the DWC common driver behaviour. > + * > + * err_m target > + * 0 NULL Return failure, function not work. > + * !0 NULL msi-map not exist, use built-in MSI. ^^^^ "function not work" does not mean anything, sorry. What is it meant to say ? !=0 > + * 0 !NULL Find one entry. > + * !0 !NULL Invalidate case. "Find one entry", "Invalidate case", I don't understand what they mean. !=0 !=NULL > + */ > + if (!err_m && !target) > + return -EINVAL; > + else if (target) > + of_node_put(target); /* Find entry for RID in msi-map */ > + > + /* > + * msi-map iommu-map > + * Y Y ITS + SMMU, require the same sid > + * Y N ITS > + * N Y DWC MSI Ctrl + SMMU > + * N N DWC MSI Ctrl > + */ > + if (!err_i && !err_m) > + if ((sid_i & IMX95_SID_MASK) != (sid_m & IMX95_SID_MASK)) { Here you mask sid_i > + dev_err(dev, "iommu-map and msi-map entries mismatch!\n"); > + return -EINVAL; > + } > + > + /* > + * Both iommu-map and msi-map not exist, use dwc built-in MSI > + * controller, do nothing here. > + */ > + if (err_i && err_m) > + return 0; > + > + if (!err_i) > + return imx_pcie_add_lut(imx_pcie, rid, sid_i); Here you don't ? Moreover - this would also cater for the case where (!err_i && !err_m) is true ? Probably cleaner to do: u32 sid; if (err_i && err_m) return 0; if (!err_i && !err_m) { if ((sid_i & IMX95_SID_MASK) != (sid_m & IMX95_SID_MASK)) { dev_err(dev, "iommu-map and msi-map entries mismatch!\n"); return -EINVAL; } } if (!err_i) sid = sid_i & IMX95_SID_MASK; else if (!err_m) sid = sid_m & IMX95_SID_MASK; return imx_pcie_add_lut(imx_pcie, rid, sid); > + else if (!err_m) > + /* > + * Hardware auto add 2 bits controller id ahead of stream ID, > + * so mask this 2bits to get stream ID. > + */ > + return imx_pcie_add_lut(imx_pcie, rid, sid_m & IMX95_SID_MASK); > + > + return 0; return 0; is dead code AFAICS. > +} > + > +static void imx_pcie_disable_device(struct pci_host_bridge *bridge, struct pci_dev *pdev) > +{ > + struct imx_pcie *imx_pcie; > + > + imx_pcie = to_imx_pcie(to_dw_pcie_from_pp(bridge->sysdata)); > + imx_pcie_remove_lut(imx_pcie, pci_dev_id(pdev)); > +} > + > static int imx_pcie_host_init(struct dw_pcie_rp *pp) > { > struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > @@ -946,6 +1119,11 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp) > } > } > > + if (pp->bridge && imx_check_flag(imx_pcie, IMX_PCIE_FLAG_HAS_LUT)) { > + pp->bridge->enable_device = imx_pcie_enable_device; > + pp->bridge->disable_device = imx_pcie_disable_device; > + } > + > imx_pcie_assert_core_reset(imx_pcie); > > if (imx_pcie->drvdata->init_phy) > @@ -1330,6 +1508,8 @@ static int imx_pcie_probe(struct platform_device *pdev) > imx_pcie->pci = pci; > imx_pcie->drvdata = of_device_get_match_data(dev); > > + mutex_init(&imx_pcie->lock); > + > /* Find the PHY if one is defined, only imx7d uses it */ > np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0); > if (np) { > @@ -1627,7 +1807,8 @@ static const struct imx_pcie_drvdata drvdata[] = { > }, > [IMX95] = { > .variant = IMX95, > - .flags = IMX_PCIE_FLAG_HAS_SERDES, > + .flags = IMX_PCIE_FLAG_HAS_SERDES | > + IMX_PCIE_FLAG_HAS_LUT, > .clk_names = imx8mq_clks, > .clks_cnt = ARRAY_SIZE(imx8mq_clks), > .ltssm_off = IMX95_PE0_GEN_CTRL_3, > > -- > 2.34.1 >