From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Emil Renner Berthing Date: Sat, 17 Jul 2021 21:50:38 +0200 Subject: pinctrl: starfive: Reset pinmux settings Current u-boot doesn't seem to take into account that some GPIOs are configured as inputs/outputs of certain peripherals on power-up. This means it ends up configuring some GPIOs as inputs to more than one peripheral which the documentation explicitly says is illegal. Similarly it also ends up configuring more than one GPIO as output of the same peripheral. While not explicitly mentioned by the documentation this also seems like a bad idea. The easiest way to remedy this mess is to just disconnect all GPIOs from peripherals and have our pinmux configuration set everything up properly. This, however, means that we'd disconnect the serial console from its pins for a while, so add a device tree property to keep certain GPIOs from being reset. Signed-off-by: Emil Renner Berthing --- Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml | 4 + drivers/pinctrl/starfive/pinctrl-starfive-jh7100.c | 66 ++++++++++ 2 files changed, 70 insertions(+) diff --git a/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml index 69c0dd9998ea..ba3a664cf2ae 100644 --- a/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml +++ b/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml @@ -88,6 +88,10 @@ properties: $ref: /schemas/types.yaml#/definitions/uint32 enum: [0, 1, 2, 3, 4, 5, 6] + starfive,keep-gpiomux: + description: Keep pinmux for these GPIOs from being reset at boot. + $ref: /schemas/types.yaml#/definitions/uint32-array + required: - compatible - reg diff --git a/drivers/pinctrl/starfive/pinctrl-starfive-jh7100.c b/drivers/pinctrl/starfive/pinctrl-starfive-jh7100.c index 5b544fb7f3d8..4230633dce26 100644 --- a/drivers/pinctrl/starfive/pinctrl-starfive-jh7100.c +++ b/drivers/pinctrl/starfive/pinctrl-starfive-jh7100.c @@ -200,6 +200,10 @@ static u16 starfive_drive_strength_from_max_mA(u32 i) return (clamp(i, 14U, 63U) - 14) / 7; } +static bool keepmux; +module_param(keepmux, bool, 0644); +MODULE_PARM_DESC(keepmux, "Keep pinmux settings from previous boot stage"); + struct starfive_pinctrl { struct gpio_chip gc; struct pinctrl_gpio_range gpios; @@ -1222,6 +1226,65 @@ static void starfive_disable_clock(void *data) clk_disable_unprepare(data); } +#define GPI_END (GPI_USB_OVER_CURRENT + 1) +static void starfive_pinmux_reset(struct starfive_pinctrl *sfp) +{ + static const DECLARE_BITMAP(defaults, GPI_END) = { + BIT_MASK(GPI_I2C0_PAD_SCK_IN) | + BIT_MASK(GPI_I2C0_PAD_SDA_IN) | + BIT_MASK(GPI_I2C1_PAD_SCK_IN) | + BIT_MASK(GPI_I2C1_PAD_SDA_IN) | + BIT_MASK(GPI_I2C2_PAD_SCK_IN) | + BIT_MASK(GPI_I2C2_PAD_SDA_IN) | + BIT_MASK(GPI_I2C3_PAD_SCK_IN) | + BIT_MASK(GPI_I2C3_PAD_SDA_IN) | + BIT_MASK(GPI_SDIO0_PAD_CARD_DETECT_N) | + + BIT_MASK(GPI_SDIO1_PAD_CARD_DETECT_N) | + BIT_MASK(GPI_SPI0_PAD_SS_IN_N) | + BIT_MASK(GPI_SPI1_PAD_SS_IN_N) | + BIT_MASK(GPI_SPI2_PAD_SS_IN_N) | + BIT_MASK(GPI_SPI2AHB_PAD_SS_N) | + BIT_MASK(GPI_SPI3_PAD_SS_IN_N), + + BIT_MASK(GPI_UART0_PAD_SIN) | + BIT_MASK(GPI_UART1_PAD_SIN) | + BIT_MASK(GPI_UART2_PAD_SIN) | + BIT_MASK(GPI_UART3_PAD_SIN) | + BIT_MASK(GPI_USB_OVER_CURRENT) + }; + DECLARE_BITMAP(keep, NR_GPIOS) = {}; + struct device_node *np = sfp->gc.parent->of_node; + int len = of_property_count_u32_elems(np, "starfive,keep-gpiomux"); + int i; + + for (i = 0; i < len; i++) { + u32 gpio; + + of_property_read_u32_index(np, "starfive,keep-gpiomux", i, &gpio); + if (gpio < NR_GPIOS) + set_bit(gpio, keep); + } + + for (i = 0; i < NR_GPIOS; i++) { + if (test_bit(i, keep)) + continue; + + writel_relaxed(GPO_DISABLE, sfp->base + GPON_DOEN_CFG + 8 * i); + writel_relaxed(GPO_LOW, sfp->base + GPON_DOUT_CFG + 8 * i); + } + + for (i = 0; i < GPI_END; i++) { + void __iomem *reg = sfp->base + GPI_CFG_OFFSET + 4 * i; + u32 din = readl_relaxed(reg); + + if (din >= 2 && din < (NR_GPIOS + 2) && test_bit(din - 2, keep)) + continue; + + writel_relaxed(test_bit(i, defaults), reg); + } +} + static int starfive_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1283,6 +1346,9 @@ static int starfive_probe(struct platform_device *pdev) writel(value, sfp->padctl + IO_PADSHARE_SEL); } + if (!keepmux) + starfive_pinmux_reset(sfp); + value = readl(sfp->padctl + IO_PADSHARE_SEL); switch (value) { case 0: -- Armbian