Hi Jacky, On Wed, Apr 12, 2023 at 05:38:22AM +0000, Jacky Huang wrote: > From: Jacky Huang <ychuang3@xxxxxxxxxxx> > > This driver supports individual IP reset for ma35d1. The reset > control registers is a subset of system control registers. > > Signed-off-by: Jacky Huang <ychuang3@xxxxxxxxxxx> > --- > drivers/reset/Kconfig | 6 + > drivers/reset/Makefile | 1 + > drivers/reset/reset-ma35d1.c | 255 +++++++++++++++++++++++++++++++++++ > 3 files changed, 262 insertions(+) > create mode 100644 drivers/reset/reset-ma35d1.c > > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > index 2a52c990d4fe..58477c6ca9b8 100644 > --- a/drivers/reset/Kconfig > +++ b/drivers/reset/Kconfig > @@ -143,6 +143,12 @@ config RESET_NPCM > This enables the reset controller driver for Nuvoton NPCM > BMC SoCs. > > +config RESET_NUVOTON_MA35D1 > + bool "Nuvton MA35D1 Reset Driver" > + default ARCH_NUVOTON || COMPILE_TEST > + help > + This enables the reset controller driver for Nuvoton MA35D1 SoC. > + > config RESET_OXNAS > bool > > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > index 3e7e5fd633a8..fd52dcf66a99 100644 > --- a/drivers/reset/Makefile > +++ b/drivers/reset/Makefile > @@ -20,6 +20,7 @@ obj-$(CONFIG_RESET_MCHP_SPARX5) += reset-microchip-sparx5.o > obj-$(CONFIG_RESET_MESON) += reset-meson.o > obj-$(CONFIG_RESET_MESON_AUDIO_ARB) += reset-meson-audio-arb.o > obj-$(CONFIG_RESET_NPCM) += reset-npcm.o > +obj-$(CONFIG_RESET_NUVOTON_MA35D1) += reset-ma35d1.o > obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o > obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o > obj-$(CONFIG_RESET_POLARFIRE_SOC) += reset-mpfs.o > diff --git a/drivers/reset/reset-ma35d1.c b/drivers/reset/reset-ma35d1.c > new file mode 100644 > index 000000000000..57ed710c10f4 > --- /dev/null > +++ b/drivers/reset/reset-ma35d1.c > @@ -0,0 +1,255 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2023 Nuvoton Technology Corp. > + * Author: Chi-Fang Li <cfli0@xxxxxxxxxxx> > + */ > + > +#include <linux/device.h> > +#include <linux/io.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/reboot.h> > +#include <linux/reset-controller.h> > +#include <dt-bindings/reset/nuvoton,ma35d1-reset.h> > + > +struct ma35d1_reset_data { > + struct reset_controller_dev rcdev; > + void __iomem *base; > +}; > + > +struct ma35d1_reboot_data { > + struct notifier_block restart_handler; > + void __iomem *base; > +}; These two structs can be combined into one, no need to duplicate the iomem base. > + > +static const struct { > + unsigned long id; Why store the id? ids should be contiguous and should start at 0, so the id could just be an index into the array. > + u32 reg_ofs; > + u32 bit; > +} ma35d1_reset_map[] = { > + { MA35D1_RESET_CHIP, 0x20, 0 }, > + { MA35D1_RESET_CA35CR0, 0x20, 1 }, > + { MA35D1_RESET_CA35CR1, 0x20, 2 }, > + { MA35D1_RESET_CM4, 0x20, 3 }, > + { MA35D1_RESET_PDMA0, 0x20, 4 }, > + { MA35D1_RESET_PDMA1, 0x20, 5 }, > + { MA35D1_RESET_PDMA2, 0x20, 6 }, > + { MA35D1_RESET_PDMA3, 0x20, 7 }, > + { MA35D1_RESET_DISP, 0x20, 9 }, > + { MA35D1_RESET_VCAP0, 0x20, 10 }, > + { MA35D1_RESET_VCAP1, 0x20, 11 }, > + { MA35D1_RESET_GFX, 0x20, 12 }, > + { MA35D1_RESET_VDEC, 0x20, 13 }, > + { MA35D1_RESET_WHC0, 0x20, 14 }, > + { MA35D1_RESET_WHC1, 0x20, 15 }, > + { MA35D1_RESET_GMAC0, 0x20, 16 }, > + { MA35D1_RESET_GMAC1, 0x20, 17 }, > + { MA35D1_RESET_HWSEM, 0x20, 18 }, > + { MA35D1_RESET_EBI, 0x20, 19 }, > + { MA35D1_RESET_HSUSBH0, 0x20, 20 }, > + { MA35D1_RESET_HSUSBH1, 0x20, 21 }, > + { MA35D1_RESET_HSUSBD, 0x20, 22 }, > + { MA35D1_RESET_USBHL, 0x20, 23 }, > + { MA35D1_RESET_SDH0, 0x20, 24 }, > + { MA35D1_RESET_SDH1, 0x20, 25 }, > + { MA35D1_RESET_NAND, 0x20, 26 }, > + { MA35D1_RESET_GPIO, 0x20, 27 }, > + { MA35D1_RESET_MCTLP, 0x20, 28 }, > + { MA35D1_RESET_MCTLC, 0x20, 29 }, > + { MA35D1_RESET_DDRPUB, 0x20, 30 }, > + { MA35D1_RESET_TMR0, 0x24, 2 }, > + { MA35D1_RESET_TMR1, 0x24, 3 }, > + { MA35D1_RESET_TMR2, 0x24, 4 }, > + { MA35D1_RESET_TMR3, 0x24, 5 }, > + { MA35D1_RESET_I2C0, 0x24, 8 }, > + { MA35D1_RESET_I2C1, 0x24, 9 }, > + { MA35D1_RESET_I2C2, 0x24, 10 }, > + { MA35D1_RESET_I2C3, 0x24, 11 }, > + { MA35D1_RESET_QSPI0, 0x24, 12 }, > + { MA35D1_RESET_SPI0, 0x24, 13 }, > + { MA35D1_RESET_SPI1, 0x24, 14 }, > + { MA35D1_RESET_SPI2, 0x24, 15 }, > + { MA35D1_RESET_UART0, 0x24, 16 }, > + { MA35D1_RESET_UART1, 0x24, 17 }, > + { MA35D1_RESET_UART2, 0x24, 18 }, > + { MA35D1_RESET_UAER3, 0x24, 19 }, > + { MA35D1_RESET_UART4, 0x24, 20 }, > + { MA35D1_RESET_UART5, 0x24, 21 }, > + { MA35D1_RESET_UART6, 0x24, 22 }, > + { MA35D1_RESET_UART7, 0x24, 23 }, > + { MA35D1_RESET_CANFD0, 0x24, 24 }, > + { MA35D1_RESET_CANFD1, 0x24, 25 }, > + { MA35D1_RESET_EADC0, 0x24, 28 }, > + { MA35D1_RESET_I2S0, 0x24, 29 }, > + { MA35D1_RESET_SC0, 0x28, 0 }, > + { MA35D1_RESET_SC1, 0x28, 1 }, > + { MA35D1_RESET_QSPI1, 0x28, 4 }, > + { MA35D1_RESET_SPI3, 0x28, 6 }, > + { MA35D1_RESET_EPWM0, 0x28, 16 }, > + { MA35D1_RESET_EPWM1, 0x28, 17 }, > + { MA35D1_RESET_QEI0, 0x28, 22 }, > + { MA35D1_RESET_QEI1, 0x28, 23 }, > + { MA35D1_RESET_ECAP0, 0x28, 26 }, > + { MA35D1_RESET_ECAP1, 0x28, 27 }, > + { MA35D1_RESET_CANFD2, 0x28, 28 }, > + { MA35D1_RESET_ADC0, 0x28, 31 }, > + { MA35D1_RESET_TMR4, 0x2C, 0 }, > + { MA35D1_RESET_TMR5, 0x2C, 1 }, > + { MA35D1_RESET_TMR6, 0x2C, 2 }, > + { MA35D1_RESET_TMR7, 0x2C, 3 }, > + { MA35D1_RESET_TMR8, 0x2C, 4 }, > + { MA35D1_RESET_TMR9, 0x2C, 5 }, > + { MA35D1_RESET_TMR10, 0x2C, 6 }, > + { MA35D1_RESET_TMR11, 0x2C, 7 }, > + { MA35D1_RESET_UART8, 0x2C, 8 }, > + { MA35D1_RESET_UART9, 0x2C, 9 }, > + { MA35D1_RESET_UART10, 0x2C, 10 }, > + { MA35D1_RESET_UART11, 0x2C, 11 }, > + { MA35D1_RESET_UART12, 0x2C, 12 }, > + { MA35D1_RESET_UART13, 0x2C, 13 }, > + { MA35D1_RESET_UART14, 0x2C, 14 }, > + { MA35D1_RESET_UART15, 0x2C, 15 }, > + { MA35D1_RESET_UART16, 0x2C, 16 }, > + { MA35D1_RESET_I2S1, 0x2C, 17 }, > + { MA35D1_RESET_I2C4, 0x2C, 18 }, > + { MA35D1_RESET_I2C5, 0x2C, 19 }, > + { MA35D1_RESET_EPWM2, 0x2C, 20 }, > + { MA35D1_RESET_ECAP2, 0x2C, 21 }, > + { MA35D1_RESET_QEI2, 0x2C, 22 }, > + { MA35D1_RESET_CANFD3, 0x2C, 23 }, > + { MA35D1_RESET_KPI, 0x2C, 24 }, > + { MA35D1_RESET_GIC, 0x2C, 28 }, > + { MA35D1_RESET_SSMCC, 0x2C, 30 }, > + { MA35D1_RESET_SSPCC, 0x2C, 31 } > +}; > + > +static u32 ma35d1_reset_map_lookup(unsigned long id) > +{ > + u32 i; > + > + for (i = 0; i < ARRAY_SIZE(ma35d1_reset_map); i++) { > + if (ma35d1_reset_map[i].id == id) > + break; > + } > + return i; > +} If you use the id as a look up into the mapping array, this lookup function wouldn't be necessary. > +static int ma35d1_restart_handler(struct notifier_block *this, > + unsigned long mode, void *cmd) > +{ > + u32 i; > + struct ma35d1_reboot_data *data = container_of(this, > + struct ma35d1_reboot_data, > + restart_handler); > + > + i = ma35d1_reset_map_lookup(MA35D1_RESET_CHIP); > + writel_relaxed(BIT(ma35d1_reset_map[i].bit), > + data->base + ma35d1_reset_map[i].reg_ofs); > + return 0; > +} > + > +static int ma35d1_reset_update(struct reset_controller_dev *rcdev, > + unsigned long id, bool assert) > +{ > + u32 i, reg; > + struct ma35d1_reset_data *data = container_of(rcdev, > + struct ma35d1_reset_data, > + rcdev); > + > + i = ma35d1_reset_map_lookup(id); > + reg = readl_relaxed(data->base + ma35d1_reset_map[i].reg_ofs); > + if (assert) > + reg |= BIT(ma35d1_reset_map[i].bit); > + else > + reg &= ~(BIT(ma35d1_reset_map[i].bit)); > + writel_relaxed(reg, data->base + ma35d1_reset_map[i].reg_ofs); This requires a spinlock to protect the register from simultaneous read-modify-writes. [...] > +static int ma35d1_reset_probe(struct platform_device *pdev) > +{ > + int err; > + struct device *dev = &pdev->dev; > + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + struct ma35d1_reset_data *reset_data; > + struct ma35d1_reboot_data *reboot_data; > + > + if (!pdev->dev.of_node) { > + dev_err(&pdev->dev, "Device tree node not found\n"); The driver is only probed via OF, so this isn't reachable and can be dropped. regards Philipp