| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Pinctrl driver for STMicroelectronics STi SoCs |
| * |
| * Copyright (C) 2017, STMicroelectronics - All Rights Reserved |
| * Author(s): Patrice Chotard, <patrice.chotard@foss.st.com> for STMicroelectronics. |
| */ |
| |
| #include <bitfield.h> |
| #include <dm.h> |
| #include <errno.h> |
| #include <regmap.h> |
| #include <syscon.h> |
| #include <asm/global_data.h> |
| #include <asm/io.h> |
| #include <dm/pinctrl.h> |
| #include <linux/bug.h> |
| #include <linux/libfdt.h> |
| #include <linux/printk.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| #define MAX_STI_PINCONF_ENTRIES 7 |
| /* Output enable */ |
| #define OE (1 << 27) |
| /* Pull Up */ |
| #define PU (1 << 26) |
| /* Open Drain */ |
| #define OD (1 << 25) |
| |
| /* User-frendly defines for Pin Direction */ |
| /* oe = 0, pu = 0, od = 0 */ |
| #define IN (0) |
| /* oe = 0, pu = 1, od = 0 */ |
| #define IN_PU (PU) |
| /* oe = 1, pu = 0, od = 0 */ |
| #define OUT (OE) |
| /* oe = 1, pu = 1, od = 0 */ |
| #define OUT_PU (OE | PU) |
| /* oe = 1, pu = 0, od = 1 */ |
| #define BIDIR (OE | OD) |
| /* oe = 1, pu = 1, od = 1 */ |
| #define BIDIR_PU (OE | PU | OD) |
| |
| struct sti_pinctrl_plat { |
| struct regmap *regmap; |
| }; |
| |
| struct sti_pin_desc { |
| unsigned char bank; |
| unsigned char pin; |
| unsigned char alt; |
| int dir; |
| }; |
| |
| /* |
| * PIO alternative Function selector |
| */ |
| void sti_alternate_select(struct udevice *dev, struct sti_pin_desc *pin_desc) |
| { |
| struct sti_pinctrl_plat *plat = dev_get_plat(dev); |
| unsigned long sysconf, *sysconfreg; |
| int alt = pin_desc->alt; |
| int bank = pin_desc->bank; |
| int pin = pin_desc->pin; |
| |
| sysconfreg = (unsigned long *)plat->regmap->ranges[0].start; |
| |
| switch (bank) { |
| case 0 ... 5: /* in "SBC Bank" */ |
| sysconfreg += bank; |
| break; |
| case 10 ... 20: /* in "FRONT Bank" */ |
| sysconfreg += bank - 10; |
| break; |
| case 30 ... 35: /* in "REAR Bank" */ |
| sysconfreg += bank - 30; |
| break; |
| case 40 ... 42: /* in "FLASH Bank" */ |
| sysconfreg += bank - 40; |
| break; |
| default: |
| BUG(); |
| return; |
| } |
| |
| sysconf = readl(sysconfreg); |
| sysconf = bitfield_replace(sysconf, pin * 4, 3, alt); |
| writel(sysconf, sysconfreg); |
| } |
| |
| /* pin configuration */ |
| void sti_pin_configure(struct udevice *dev, struct sti_pin_desc *pin_desc) |
| { |
| struct sti_pinctrl_plat *plat = dev_get_plat(dev); |
| int bit; |
| int oe = 0, pu = 0, od = 0; |
| unsigned long *sysconfreg; |
| int bank = pin_desc->bank; |
| |
| sysconfreg = (unsigned long *)plat->regmap->ranges[0].start + 40; |
| |
| /* |
| * NOTE: The PIO configuration for the PIO pins in the |
| * "FLASH Bank" are different from all the other banks! |
| * Specifically, the output-enable pin control register |
| * (SYS_CFG_3040) and the pull-up pin control register |
| * (SYS_CFG_3050), are both classed as being "reserved". |
| * Hence, we do not write to these registers to configure |
| * the OE and PU features for PIOs in this bank. However, |
| * the open-drain pin control register (SYS_CFG_3060) |
| * follows the style of the other banks, and so we can |
| * treat that register normally. |
| * |
| * Being pedantic, we should configure the PU and PD features |
| * in the "FLASH Bank" explicitly instead using the four |
| * SYS_CFG registers: 3080, 3081, 3085, and 3086. However, this |
| * would necessitate passing in the alternate function number |
| * to this function, and adding some horrible complexity here. |
| * Alternatively, we could just perform 4 32-bit "pokes" to |
| * these four SYS_CFG registers early in the initialization. |
| * In practice, these four SYS_CFG registers are correct |
| * after a reset, and U-Boot does not need to change them, so |
| * we (cheat and) rely on these registers being correct. |
| * WARNING: Please be aware of this (pragmatic) behaviour! |
| */ |
| int flashss = 0; /* bool: PIO in the Flash Sub-System ? */ |
| |
| switch (pin_desc->dir) { |
| case IN: |
| oe = 0; pu = 0; od = 0; |
| break; |
| case IN_PU: |
| oe = 0; pu = 1; od = 0; |
| break; |
| case OUT: |
| oe = 1; pu = 0; od = 0; |
| break; |
| case BIDIR: |
| oe = 1; pu = 0; od = 1; |
| break; |
| case BIDIR_PU: |
| oe = 1; pu = 1; od = 1; |
| break; |
| |
| default: |
| pr_err("%s invalid direction value: 0x%x\n", |
| __func__, pin_desc->dir); |
| BUG(); |
| break; |
| } |
| |
| switch (bank) { |
| case 0 ... 5: /* in "SBC Bank" */ |
| sysconfreg += bank / 4; |
| break; |
| case 10 ... 20: /* in "FRONT Bank" */ |
| bank -= 10; |
| sysconfreg += bank / 4; |
| break; |
| case 30 ... 35: /* in "REAR Bank" */ |
| bank -= 30; |
| sysconfreg += bank / 4; |
| break; |
| case 40 ... 42: /* in "FLASH Bank" */ |
| bank -= 40; |
| sysconfreg += bank / 4; |
| flashss = 1; /* pin is in the Flash Sub-System */ |
| break; |
| default: |
| BUG(); |
| return; |
| } |
| |
| bit = ((bank * 8) + pin_desc->pin) % 32; |
| |
| /* |
| * set the "Output Enable" pin control |
| * but, do nothing if in the flashSS |
| */ |
| if (!flashss) { |
| if (oe) |
| generic_set_bit(bit, sysconfreg); |
| else |
| generic_clear_bit(bit, sysconfreg); |
| } |
| |
| sysconfreg += 10; /* skip to next set of syscfg registers */ |
| |
| /* |
| * set the "Pull Up" pin control |
| * but, do nothing if in the FlashSS |
| */ |
| |
| if (!flashss) { |
| if (pu) |
| generic_set_bit(bit, sysconfreg); |
| else |
| generic_clear_bit(bit, sysconfreg); |
| } |
| |
| sysconfreg += 10; /* skip to next set of syscfg registers */ |
| |
| /* set the "Open Drain Enable" pin control */ |
| if (od) |
| generic_set_bit(bit, sysconfreg); |
| else |
| generic_clear_bit(bit, sysconfreg); |
| } |
| |
| static int sti_pinctrl_set_state(struct udevice *dev, struct udevice *config) |
| { |
| struct fdtdec_phandle_args args; |
| const void *blob = gd->fdt_blob; |
| const char *prop_name; |
| int node = dev_of_offset(config); |
| int property_offset, prop_len; |
| int pinconf_node, ret, count; |
| const char *bank_name; |
| u32 cells[MAX_STI_PINCONF_ENTRIES]; |
| |
| struct sti_pin_desc pin_desc; |
| |
| /* go to next node "st,pins" which contains the pins configuration */ |
| pinconf_node = fdt_subnode_offset(blob, node, "st,pins"); |
| |
| /* |
| * parse each pins configuration which looks like : |
| * pin_name = <bank_phandle pin_nb alt dir rt_type rt_delay rt_clk> |
| */ |
| |
| fdt_for_each_property_offset(property_offset, blob, pinconf_node) { |
| fdt_getprop_by_offset(blob, property_offset, &prop_name, |
| &prop_len); |
| |
| /* extract the bank of the pin description */ |
| ret = fdtdec_parse_phandle_with_args(blob, pinconf_node, |
| prop_name, "#gpio-cells", |
| 0, 0, &args); |
| if (ret < 0) { |
| pr_err("Can't get the gpio bank phandle: %d\n", ret); |
| return ret; |
| } |
| |
| bank_name = fdt_getprop(blob, args.node, "st,bank-name", |
| &count); |
| if (count < 0) { |
| pr_err("Can't find bank-name property %d\n", count); |
| return -EINVAL; |
| } |
| |
| pin_desc.bank = trailing_strtoln(bank_name, NULL); |
| |
| count = fdtdec_get_int_array_count(blob, pinconf_node, |
| prop_name, cells, |
| ARRAY_SIZE(cells)); |
| if (count < 0) { |
| pr_err("Bad pin configuration array %d\n", count); |
| return -EINVAL; |
| } |
| |
| if (count > MAX_STI_PINCONF_ENTRIES) { |
| pr_err("Unsupported pinconf array count %d\n", count); |
| return -EINVAL; |
| } |
| |
| pin_desc.pin = cells[1]; |
| pin_desc.alt = cells[2]; |
| pin_desc.dir = cells[3]; |
| |
| sti_alternate_select(dev, &pin_desc); |
| sti_pin_configure(dev, &pin_desc); |
| }; |
| |
| return 0; |
| } |
| |
| static int sti_pinctrl_probe(struct udevice *dev) |
| { |
| struct sti_pinctrl_plat *plat = dev_get_plat(dev); |
| struct udevice *syscon; |
| int err; |
| |
| /* get corresponding syscon phandle */ |
| err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev, |
| "st,syscfg", &syscon); |
| if (err) { |
| pr_err("unable to find syscon device\n"); |
| return err; |
| } |
| |
| plat->regmap = syscon_get_regmap(syscon); |
| if (!plat->regmap) { |
| pr_err("unable to find regmap\n"); |
| return -ENODEV; |
| } |
| |
| return 0; |
| } |
| |
| static const struct udevice_id sti_pinctrl_ids[] = { |
| { .compatible = "st,stih407-sbc-pinctrl" }, |
| { .compatible = "st,stih407-front-pinctrl" }, |
| { .compatible = "st,stih407-rear-pinctrl" }, |
| { .compatible = "st,stih407-flash-pinctrl" }, |
| { } |
| }; |
| |
| const struct pinctrl_ops sti_pinctrl_ops = { |
| .set_state = sti_pinctrl_set_state, |
| }; |
| |
| U_BOOT_DRIVER(pinctrl_sti) = { |
| .name = "pinctrl_sti", |
| .id = UCLASS_PINCTRL, |
| .of_match = sti_pinctrl_ids, |
| .ops = &sti_pinctrl_ops, |
| .probe = sti_pinctrl_probe, |
| .plat_auto = sizeof(struct sti_pinctrl_plat), |
| .ops = &sti_pinctrl_ops, |
| }; |