Krzysztof Kozlowski | f12bb916 | 2018-01-09 19:29:55 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // |
| 3 | // Copyright (c) 2015 Samsung Electronics Co., Ltd. |
| 4 | // http://www.samsung.com/ |
| 5 | // |
| 6 | // EXYNOS - SROM Controller support |
| 7 | // Author: Pankaj Dubey <pankaj.dubey@samsung.com> |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 8 | |
| 9 | #include <linux/io.h> |
Paul Gortmaker | 58f388b | 2016-06-16 20:37:47 -0400 | [diff] [blame] | 10 | #include <linux/init.h> |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 11 | #include <linux/of.h> |
| 12 | #include <linux/of_address.h> |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 13 | #include <linux/of_platform.h> |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 14 | #include <linux/platform_device.h> |
| 15 | #include <linux/slab.h> |
| 16 | |
| 17 | #include "exynos-srom.h" |
| 18 | |
| 19 | static const unsigned long exynos_srom_offsets[] = { |
| 20 | /* SROM side */ |
| 21 | EXYNOS_SROM_BW, |
| 22 | EXYNOS_SROM_BC0, |
| 23 | EXYNOS_SROM_BC1, |
| 24 | EXYNOS_SROM_BC2, |
| 25 | EXYNOS_SROM_BC3, |
| 26 | }; |
| 27 | |
| 28 | /** |
| 29 | * struct exynos_srom_reg_dump: register dump of SROM Controller registers. |
| 30 | * @offset: srom register offset from the controller base address. |
| 31 | * @value: the value of register under the offset. |
| 32 | */ |
| 33 | struct exynos_srom_reg_dump { |
| 34 | u32 offset; |
| 35 | u32 value; |
| 36 | }; |
| 37 | |
| 38 | /** |
| 39 | * struct exynos_srom: platform data for exynos srom controller driver. |
| 40 | * @dev: platform device pointer |
| 41 | * @reg_base: srom base address |
| 42 | * @reg_offset: exynos_srom_reg_dump pointer to hold offset and its value. |
| 43 | */ |
| 44 | struct exynos_srom { |
| 45 | struct device *dev; |
| 46 | void __iomem *reg_base; |
| 47 | struct exynos_srom_reg_dump *reg_offset; |
| 48 | }; |
| 49 | |
| 50 | static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump( |
| 51 | const unsigned long *rdump, |
| 52 | unsigned long nr_rdump) |
| 53 | { |
| 54 | struct exynos_srom_reg_dump *rd; |
| 55 | unsigned int i; |
| 56 | |
| 57 | rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL); |
| 58 | if (!rd) |
| 59 | return NULL; |
| 60 | |
| 61 | for (i = 0; i < nr_rdump; ++i) |
| 62 | rd[i].offset = rdump[i]; |
| 63 | |
| 64 | return rd; |
| 65 | } |
| 66 | |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 67 | static int exynos_srom_configure_bank(struct exynos_srom *srom, |
| 68 | struct device_node *np) |
| 69 | { |
| 70 | u32 bank, width, pmc = 0; |
| 71 | u32 timing[6]; |
| 72 | u32 cs, bw; |
| 73 | |
| 74 | if (of_property_read_u32(np, "reg", &bank)) |
| 75 | return -EINVAL; |
| 76 | if (of_property_read_u32(np, "reg-io-width", &width)) |
| 77 | width = 1; |
| 78 | if (of_property_read_bool(np, "samsung,srom-page-mode")) |
| 79 | pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT; |
| 80 | if (of_property_read_u32_array(np, "samsung,srom-timing", timing, |
| 81 | ARRAY_SIZE(timing))) |
| 82 | return -EINVAL; |
| 83 | |
| 84 | bank *= 4; /* Convert bank into shift/offset */ |
| 85 | |
| 86 | cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT; |
| 87 | if (width == 2) |
| 88 | cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT; |
| 89 | |
Ben Dooks | cbf7317 | 2016-06-17 18:08:10 +0100 | [diff] [blame] | 90 | bw = readl_relaxed(srom->reg_base + EXYNOS_SROM_BW); |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 91 | bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank); |
Ben Dooks | cbf7317 | 2016-06-17 18:08:10 +0100 | [diff] [blame] | 92 | writel_relaxed(bw, srom->reg_base + EXYNOS_SROM_BW); |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 93 | |
Ben Dooks | cbf7317 | 2016-06-17 18:08:10 +0100 | [diff] [blame] | 94 | writel_relaxed(pmc | (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) | |
| 95 | (timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) | |
| 96 | (timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) | |
| 97 | (timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) | |
| 98 | (timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) | |
| 99 | (timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT), |
| 100 | srom->reg_base + EXYNOS_SROM_BC0 + bank); |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 101 | |
| 102 | return 0; |
| 103 | } |
| 104 | |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 105 | static int exynos_srom_probe(struct platform_device *pdev) |
| 106 | { |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 107 | struct device_node *np, *child; |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 108 | struct exynos_srom *srom; |
| 109 | struct device *dev = &pdev->dev; |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 110 | bool bad_bank_config = false; |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 111 | |
| 112 | np = dev->of_node; |
| 113 | if (!np) { |
| 114 | dev_err(&pdev->dev, "could not find device info\n"); |
| 115 | return -EINVAL; |
| 116 | } |
| 117 | |
| 118 | srom = devm_kzalloc(&pdev->dev, |
| 119 | sizeof(struct exynos_srom), GFP_KERNEL); |
| 120 | if (!srom) |
| 121 | return -ENOMEM; |
| 122 | |
| 123 | srom->dev = dev; |
| 124 | srom->reg_base = of_iomap(np, 0); |
| 125 | if (!srom->reg_base) { |
| 126 | dev_err(&pdev->dev, "iomap of exynos srom controller failed\n"); |
| 127 | return -ENOMEM; |
| 128 | } |
| 129 | |
| 130 | platform_set_drvdata(pdev, srom); |
| 131 | |
| 132 | srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets, |
Seung-Woo Kim | 24c4b47 | 2016-07-05 20:40:17 +0900 | [diff] [blame] | 133 | ARRAY_SIZE(exynos_srom_offsets)); |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 134 | if (!srom->reg_offset) { |
| 135 | iounmap(srom->reg_base); |
| 136 | return -ENOMEM; |
| 137 | } |
| 138 | |
Pavel Fedin | 8ac2266 | 2016-04-11 13:12:27 +0530 | [diff] [blame] | 139 | for_each_child_of_node(np, child) { |
| 140 | if (exynos_srom_configure_bank(srom, child)) { |
| 141 | dev_err(dev, |
| 142 | "Could not decode bank configuration for %s\n", |
| 143 | child->name); |
| 144 | bad_bank_config = true; |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * If any bank failed to configure, we still provide suspend/resume, |
| 150 | * but do not probe child devices |
| 151 | */ |
| 152 | if (bad_bank_config) |
| 153 | return 0; |
| 154 | |
| 155 | return of_platform_populate(np, NULL, NULL, dev); |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 156 | } |
| 157 | |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 158 | #ifdef CONFIG_PM_SLEEP |
| 159 | static void exynos_srom_save(void __iomem *base, |
| 160 | struct exynos_srom_reg_dump *rd, |
| 161 | unsigned int num_regs) |
| 162 | { |
| 163 | for (; num_regs > 0; --num_regs, ++rd) |
| 164 | rd->value = readl(base + rd->offset); |
| 165 | } |
| 166 | |
| 167 | static void exynos_srom_restore(void __iomem *base, |
| 168 | const struct exynos_srom_reg_dump *rd, |
| 169 | unsigned int num_regs) |
| 170 | { |
| 171 | for (; num_regs > 0; --num_regs, ++rd) |
| 172 | writel(rd->value, base + rd->offset); |
| 173 | } |
| 174 | |
| 175 | static int exynos_srom_suspend(struct device *dev) |
| 176 | { |
| 177 | struct exynos_srom *srom = dev_get_drvdata(dev); |
| 178 | |
| 179 | exynos_srom_save(srom->reg_base, srom->reg_offset, |
| 180 | ARRAY_SIZE(exynos_srom_offsets)); |
| 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | static int exynos_srom_resume(struct device *dev) |
| 185 | { |
| 186 | struct exynos_srom *srom = dev_get_drvdata(dev); |
| 187 | |
| 188 | exynos_srom_restore(srom->reg_base, srom->reg_offset, |
| 189 | ARRAY_SIZE(exynos_srom_offsets)); |
| 190 | return 0; |
| 191 | } |
| 192 | #endif |
| 193 | |
| 194 | static const struct of_device_id of_exynos_srom_ids[] = { |
| 195 | { |
| 196 | .compatible = "samsung,exynos4210-srom", |
| 197 | }, |
| 198 | {}, |
| 199 | }; |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 200 | |
| 201 | static SIMPLE_DEV_PM_OPS(exynos_srom_pm_ops, exynos_srom_suspend, exynos_srom_resume); |
| 202 | |
| 203 | static struct platform_driver exynos_srom_driver = { |
| 204 | .probe = exynos_srom_probe, |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 205 | .driver = { |
| 206 | .name = "exynos-srom", |
| 207 | .of_match_table = of_exynos_srom_ids, |
| 208 | .pm = &exynos_srom_pm_ops, |
Paul Gortmaker | 58f388b | 2016-06-16 20:37:47 -0400 | [diff] [blame] | 209 | .suppress_bind_attrs = true, |
Pankaj Dubey | a8aabb9 | 2016-04-11 13:12:24 +0530 | [diff] [blame] | 210 | }, |
| 211 | }; |
Paul Gortmaker | 58f388b | 2016-06-16 20:37:47 -0400 | [diff] [blame] | 212 | builtin_platform_driver(exynos_srom_driver); |