// SPDX-License-Identifier: GPL-2.0+ /* * Pinctrl driver for STMicroelectronics STi SoCs * * Copyright (C) 2017, STMicroelectronics - All Rights Reserved * Author(s): Patrice Chotard, for STMicroelectronics. */ #include #include #include #include #include #include #include #include #include #include #include #include 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 = */ 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, };