| Message ID | 20181119094144.4127-2-stefan@agner.ch |
|---|---|
| State | Superseded |
| Delegated to: | Lorenzo Pieralisi |
| Headers | show |
| Series | [1/2] PCI: dwc: allow to limit registers set length | expand |
On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: > Define the length of the DBI registers. This makes sure that > the kernel does not access registers beyond that point, avoiding > the following abort on a i.MX 6Quad: > # cat > /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config > [ 100.021433] Unhandled fault: imprecise external abort (0x1406) > at 0xb6ea7000 > ... > [ 100.056423] PC is at dw_pcie_read+0x50/0x84 > [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 > ... > > Signed-off-by: Stefan Agner <stefan@agner.ch> After updating this for v4.20-rc2, tested on IMX 7d, config space access works as before. Tested-by: Trent Piepho <tpiepho@impinj.com>
On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: > > > +static const struct imx6_pcie_drvdata imx6q_pcie_drvdata = { > + .variant = IMX6Q, > + .dbi_length = 0x15c, > +}; > + > +static const struct imx6_pcie_drvdata imx6sx_pcie_drvdata = { > + .variant = IMX6SX, > +}; > + > +static const struct imx6_pcie_drvdata imx6qp_pcie_drvdata = { > + .variant = IMX6QP, > +}; > + > +static const struct imx6_pcie_drvdata imx7d_pcie_drvdata = { > + .variant = IMX7D, > +}; > + > static const struct of_device_id imx6_pcie_of_match[] = { > - { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, }, > - { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, }, > - { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, }, > - { .compatible = "fsl,imx7d-pcie", .data = (void *)IMX7D, }, > + { .compatible = "fsl,imx6q-pcie", .data = &imx6q_pcie_drvdata, }, > + { .compatible = "fsl,imx6sx-pcie", .data = &imx6sx_pcie_drvdata, }, > + { .compatible = "fsl,imx6qp-pcie", .data = &imx6qp_pcie_drvdata, }, > + { .compatible = "fsl,imx7d-pcie", .data = &imx7d_pcie_drvdata, }, > {}, > }; Instead of making a single drvdata struct for each type, this could use an array: static const struct imx6_pcie_drvdata drvdata[] = { [IMX6Q] = { .variant = IMX6Q, .dbi_length = 0x15c }, [IMX6SX] = { .variant = IMX6SX }, [...] }; static const struct of_device_id imx6_pcie_of_match[] = { { .compatible = "fsl,imx6q-pcie", .data = &drvdata[IMX6Q], }, { .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], }, ... };
On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: > Define the length of the DBI registers. This makes sure that > the kernel does not access registers beyond that point, avoiding > the following abort on a i.MX 6Quad: > # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config > [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000 > ... > [ 100.056423] PC is at dw_pcie_read+0x50/0x84 > [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 > ... > > Signed-off-by: Stefan Agner <stefan@agner.ch> > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c > +struct imx6_pcie_drvdata { > + enum imx6_pcie_variants variant; > + int dbi_length; > +}; Turning imx6_pcie drvdata into a struct is very nice, maybe in the future some of the long case statements in this driver could be split into per-soc functions called via drvdata.
On 20.11.2018 11:22, Leonard Crestez wrote: > On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: >> Define the length of the DBI registers. This makes sure that >> the kernel does not access registers beyond that point, avoiding >> the following abort on a i.MX 6Quad: >> # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config >> [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000 >> ... >> [ 100.056423] PC is at dw_pcie_read+0x50/0x84 >> [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 >> ... >> >> Signed-off-by: Stefan Agner <stefan@agner.ch> >> >> diff --git a/drivers/pci/controller/dwc/pci-imx6.c > >> +struct imx6_pcie_drvdata { >> + enum imx6_pcie_variants variant; >> + int dbi_length; >> +}; > > Turning imx6_pcie drvdata into a struct is very nice, maybe in the > future some of the long case statements in this driver could be split > into per-soc functions called via drvdata. Yeah I thought that too. At a quick glance I did not saw an obvious contender. Should certainly help for similar cases in the future. -- Stefan
From: Stefan Agner <stefan@agner.ch> > On 20.11.2018 11:22, Leonard Crestez wrote: > > On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: > >> Define the length of the DBI registers. This makes sure that > >> the kernel does not access registers beyond that point, avoiding > >> the following abort on a i.MX 6Quad: > >> # cat > /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config > >> [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at > 0xb6ea7000 > >> ... > >> [ 100.056423] PC is at dw_pcie_read+0x50/0x84 > >> [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 > >> ... > >> > >> Signed-off-by: Stefan Agner <stefan@agner.ch> > >> > >> diff --git a/drivers/pci/controller/dwc/pci-imx6.c > > > >> +struct imx6_pcie_drvdata { > >> + enum imx6_pcie_variants variant; > >> + int dbi_length; > >> +}; > > > > Turning imx6_pcie drvdata into a struct is very nice, maybe in the > > future some of the long case statements in this driver could be split > > into per-soc functions called via drvdata. > > Yeah I thought that too. At a quick glance I did not saw an obvious > contender. Should certainly help for similar cases in the future. Yes, there are other cases in which it would be useful. But I think it makes more sense to split introducing drvdata to a separate patch. It's nice to separate functional and code cleanup changes. For example maybe dbi_length causes issues and has to be reverted? -- Regards, Leonard
On 20.11.2018 14:03, Leonard Crestez wrote: > From: Stefan Agner <stefan@agner.ch> >> On 20.11.2018 11:22, Leonard Crestez wrote: >> > On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote: >> >> Define the length of the DBI registers. This makes sure that >> >> the kernel does not access registers beyond that point, avoiding >> >> the following abort on a i.MX 6Quad: >> >> # cat >> /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config >> >> [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at >> 0xb6ea7000 >> >> ... >> >> [ 100.056423] PC is at dw_pcie_read+0x50/0x84 >> >> [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 >> >> ... >> >> >> >> Signed-off-by: Stefan Agner <stefan@agner.ch> >> >> >> >> diff --git a/drivers/pci/controller/dwc/pci-imx6.c >> > >> >> +struct imx6_pcie_drvdata { >> >> + enum imx6_pcie_variants variant; >> >> + int dbi_length; >> >> +}; >> > >> > Turning imx6_pcie drvdata into a struct is very nice, maybe in the >> > future some of the long case statements in this driver could be split >> > into per-soc functions called via drvdata. >> >> Yeah I thought that too. At a quick glance I did not saw an obvious >> contender. Should certainly help for similar cases in the future. > > Yes, there are other cases in which it would be useful. > > But I think it makes more sense to split introducing drvdata to a > separate patch. > It's nice to separate functional and code cleanup changes. > > For example maybe dbi_length causes issues and has to be reverted? Ok, makes sense, will split drvdata introduction in its own patch. -- Stefan
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 4a9a673b4777..8c96af414dac 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -39,6 +39,11 @@ enum imx6_pcie_variants { IMX7D, }; +struct imx6_pcie_drvdata { + enum imx6_pcie_variants variant; + int dbi_length; +}; + struct imx6_pcie { struct dw_pcie *pci; int reset_gpio; @@ -50,7 +55,6 @@ struct imx6_pcie { struct regmap *iomuxc_gpr; struct reset_control *pciephy_reset; struct reset_control *apps_reset; - enum imx6_pcie_variants variant; u32 tx_deemph_gen1; u32 tx_deemph_gen2_3p5db; u32 tx_deemph_gen2_6db; @@ -58,6 +62,7 @@ struct imx6_pcie { u32 tx_swing_low; int link_gen; struct regulator *vpcie; + const struct imx6_pcie_drvdata *drvdata; }; /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ @@ -285,7 +290,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) { struct device *dev = imx6_pcie->pci->dev; - switch (imx6_pcie->variant) { + switch (imx6_pcie->drvdata->variant) { case IMX7D: reset_control_assert(imx6_pcie->pciephy_reset); reset_control_assert(imx6_pcie->apps_reset); @@ -327,7 +332,7 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) struct device *dev = pci->dev; int ret = 0; - switch (imx6_pcie->variant) { + switch (imx6_pcie->drvdata->variant) { case IMX6SX: ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi); if (ret) { @@ -430,7 +435,7 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) !imx6_pcie->gpio_active_high); } - switch (imx6_pcie->variant) { + switch (imx6_pcie->drvdata->variant) { case IMX7D: reset_control_deassert(imx6_pcie->pciephy_reset); imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie); @@ -468,7 +473,7 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) { - switch (imx6_pcie->variant) { + switch (imx6_pcie->drvdata->variant) { case IMX7D: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0); @@ -560,7 +565,7 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); /* Start LTSSM. */ - if (imx6_pcie->variant == IMX7D) + if (imx6_pcie->drvdata->variant == IMX7D) reset_control_deassert(imx6_pcie->apps_reset); else regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, @@ -585,7 +590,7 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) tmp |= PORT_LOGIC_SPEED_CHANGE; dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); - if (imx6_pcie->variant != IMX7D) { + if (imx6_pcie->drvdata->variant != IMX7D) { /* * On i.MX7, DIRECT_SPEED_CHANGE behaves differently * from i.MX6 family when no link speed transition @@ -703,8 +708,7 @@ static int imx6_pcie_probe(struct platform_device *pdev) pci->ops = &dw_pcie_ops; imx6_pcie->pci = pci; - imx6_pcie->variant = - (enum imx6_pcie_variants)of_device_get_match_data(dev); + imx6_pcie->drvdata = of_device_get_match_data(dev); dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); pci->dbi_base = devm_ioremap_resource(dev, dbi_base); @@ -748,7 +752,7 @@ static int imx6_pcie_probe(struct platform_device *pdev) return PTR_ERR(imx6_pcie->pcie); } - switch (imx6_pcie->variant) { + switch (imx6_pcie->drvdata->variant) { case IMX6SX: imx6_pcie->pcie_inbound_axi = devm_clk_get(dev, "pcie_inbound_axi"); @@ -776,6 +780,8 @@ static int imx6_pcie_probe(struct platform_device *pdev) break; } + pci->dbi_length = imx6_pcie->drvdata->dbi_length; + /* Grab GPR config register range */ imx6_pcie->iomuxc_gpr = syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr"); @@ -835,11 +841,28 @@ static void imx6_pcie_shutdown(struct platform_device *pdev) imx6_pcie_assert_core_reset(imx6_pcie); } +static const struct imx6_pcie_drvdata imx6q_pcie_drvdata = { + .variant = IMX6Q, + .dbi_length = 0x15c, +}; + +static const struct imx6_pcie_drvdata imx6sx_pcie_drvdata = { + .variant = IMX6SX, +}; + +static const struct imx6_pcie_drvdata imx6qp_pcie_drvdata = { + .variant = IMX6QP, +}; + +static const struct imx6_pcie_drvdata imx7d_pcie_drvdata = { + .variant = IMX7D, +}; + static const struct of_device_id imx6_pcie_of_match[] = { - { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, }, - { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, }, - { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, }, - { .compatible = "fsl,imx7d-pcie", .data = (void *)IMX7D, }, + { .compatible = "fsl,imx6q-pcie", .data = &imx6q_pcie_drvdata, }, + { .compatible = "fsl,imx6sx-pcie", .data = &imx6sx_pcie_drvdata, }, + { .compatible = "fsl,imx6qp-pcie", .data = &imx6qp_pcie_drvdata, }, + { .compatible = "fsl,imx7d-pcie", .data = &imx7d_pcie_drvdata, }, {}, };
Define the length of the DBI registers. This makes sure that the kernel does not access registers beyond that point, avoiding the following abort on a i.MX 6Quad: # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000 ... [ 100.056423] PC is at dw_pcie_read+0x50/0x84 [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48 ... Signed-off-by: Stefan Agner <stefan@agner.ch> --- drivers/pci/controller/dwc/pci-imx6.c | 51 +++++++++++++++++++-------- 1 file changed, 37 insertions(+), 14 deletions(-)