18caef1faSMartin Blumenstingl /* 28caef1faSMartin Blumenstingl * Amlogic Meson6, Meson8 and Meson8b eFuse Driver 38caef1faSMartin Blumenstingl * 48caef1faSMartin Blumenstingl * Copyright (c) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com> 58caef1faSMartin Blumenstingl * 68caef1faSMartin Blumenstingl * This program is free software; you can redistribute it and/or modify it 78caef1faSMartin Blumenstingl * under the terms of version 2 of the GNU General Public License as 88caef1faSMartin Blumenstingl * published by the Free Software Foundation. 98caef1faSMartin Blumenstingl * 108caef1faSMartin Blumenstingl * This program is distributed in the hope that it will be useful, but WITHOUT 118caef1faSMartin Blumenstingl * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 128caef1faSMartin Blumenstingl * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 138caef1faSMartin Blumenstingl * more details. 148caef1faSMartin Blumenstingl */ 158caef1faSMartin Blumenstingl 168caef1faSMartin Blumenstingl #include <linux/bitfield.h> 178caef1faSMartin Blumenstingl #include <linux/bitops.h> 188caef1faSMartin Blumenstingl #include <linux/clk.h> 198caef1faSMartin Blumenstingl #include <linux/delay.h> 208caef1faSMartin Blumenstingl #include <linux/io.h> 218caef1faSMartin Blumenstingl #include <linux/iopoll.h> 228caef1faSMartin Blumenstingl #include <linux/module.h> 238caef1faSMartin Blumenstingl #include <linux/nvmem-provider.h> 248caef1faSMartin Blumenstingl #include <linux/of.h> 258caef1faSMartin Blumenstingl #include <linux/of_device.h> 268caef1faSMartin Blumenstingl #include <linux/platform_device.h> 278caef1faSMartin Blumenstingl #include <linux/sizes.h> 288caef1faSMartin Blumenstingl #include <linux/slab.h> 298caef1faSMartin Blumenstingl 308caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1 0x04 318caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_PD_ENABLE BIT(27) 328caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_RD_BUSY BIT(26) 338caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_RD_START BIT(25) 348caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_RD_ENABLE BIT(24) 358caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_BYTE_WR_DATA GENMASK(23, 16) 368caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_WR_BUSY BIT(14) 378caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_WR_START BIT(13) 388caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_AUTO_WR_ENABLE BIT(12) 398caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_BYTE_ADDR_SET BIT(11) 408caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL1_BYTE_ADDR_MASK GENMASK(10, 0) 418caef1faSMartin Blumenstingl 428caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL2 0x08 438caef1faSMartin Blumenstingl 448caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL4 0x10 458caef1faSMartin Blumenstingl #define MESON_MX_EFUSE_CNTL4_ENCRYPT_ENABLE BIT(10) 468caef1faSMartin Blumenstingl 478caef1faSMartin Blumenstingl struct meson_mx_efuse_platform_data { 488caef1faSMartin Blumenstingl const char *name; 498caef1faSMartin Blumenstingl unsigned int word_size; 508caef1faSMartin Blumenstingl }; 518caef1faSMartin Blumenstingl 528caef1faSMartin Blumenstingl struct meson_mx_efuse { 538caef1faSMartin Blumenstingl void __iomem *base; 548caef1faSMartin Blumenstingl struct clk *core_clk; 558caef1faSMartin Blumenstingl struct nvmem_device *nvmem; 568caef1faSMartin Blumenstingl struct nvmem_config config; 578caef1faSMartin Blumenstingl }; 588caef1faSMartin Blumenstingl 598caef1faSMartin Blumenstingl static void meson_mx_efuse_mask_bits(struct meson_mx_efuse *efuse, u32 reg, 608caef1faSMartin Blumenstingl u32 mask, u32 set) 618caef1faSMartin Blumenstingl { 628caef1faSMartin Blumenstingl u32 data; 638caef1faSMartin Blumenstingl 648caef1faSMartin Blumenstingl data = readl(efuse->base + reg); 658caef1faSMartin Blumenstingl data &= ~mask; 668caef1faSMartin Blumenstingl data |= (set & mask); 678caef1faSMartin Blumenstingl 688caef1faSMartin Blumenstingl writel(data, efuse->base + reg); 698caef1faSMartin Blumenstingl } 708caef1faSMartin Blumenstingl 718caef1faSMartin Blumenstingl static int meson_mx_efuse_hw_enable(struct meson_mx_efuse *efuse) 728caef1faSMartin Blumenstingl { 738caef1faSMartin Blumenstingl int err; 748caef1faSMartin Blumenstingl 758caef1faSMartin Blumenstingl err = clk_prepare_enable(efuse->core_clk); 768caef1faSMartin Blumenstingl if (err) 778caef1faSMartin Blumenstingl return err; 788caef1faSMartin Blumenstingl 798caef1faSMartin Blumenstingl /* power up the efuse */ 808caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 818caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_PD_ENABLE, 0); 828caef1faSMartin Blumenstingl 838caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL4, 848caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL4_ENCRYPT_ENABLE, 0); 858caef1faSMartin Blumenstingl 868caef1faSMartin Blumenstingl return 0; 878caef1faSMartin Blumenstingl } 888caef1faSMartin Blumenstingl 898caef1faSMartin Blumenstingl static void meson_mx_efuse_hw_disable(struct meson_mx_efuse *efuse) 908caef1faSMartin Blumenstingl { 918caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 928caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_PD_ENABLE, 938caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_PD_ENABLE); 948caef1faSMartin Blumenstingl 958caef1faSMartin Blumenstingl clk_disable_unprepare(efuse->core_clk); 968caef1faSMartin Blumenstingl } 978caef1faSMartin Blumenstingl 988caef1faSMartin Blumenstingl static int meson_mx_efuse_read_addr(struct meson_mx_efuse *efuse, 998caef1faSMartin Blumenstingl unsigned int addr, u32 *value) 1008caef1faSMartin Blumenstingl { 1018caef1faSMartin Blumenstingl int err; 1028caef1faSMartin Blumenstingl u32 regval; 1038caef1faSMartin Blumenstingl 1048caef1faSMartin Blumenstingl /* write the address to read */ 1058caef1faSMartin Blumenstingl regval = FIELD_PREP(MESON_MX_EFUSE_CNTL1_BYTE_ADDR_MASK, addr); 1068caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1078caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_BYTE_ADDR_MASK, regval); 1088caef1faSMartin Blumenstingl 1098caef1faSMartin Blumenstingl /* inform the hardware that we changed the address */ 1108caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1118caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_BYTE_ADDR_SET, 1128caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_BYTE_ADDR_SET); 1138caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1148caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_BYTE_ADDR_SET, 0); 1158caef1faSMartin Blumenstingl 1168caef1faSMartin Blumenstingl /* start the read process */ 1178caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1188caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_START, 1198caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_START); 1208caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1218caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_START, 0); 1228caef1faSMartin Blumenstingl 1238caef1faSMartin Blumenstingl /* 1248caef1faSMartin Blumenstingl * perform a dummy read to ensure that the HW has the RD_BUSY bit set 1258caef1faSMartin Blumenstingl * when polling for the status below. 1268caef1faSMartin Blumenstingl */ 1278caef1faSMartin Blumenstingl readl(efuse->base + MESON_MX_EFUSE_CNTL1); 1288caef1faSMartin Blumenstingl 1298caef1faSMartin Blumenstingl err = readl_poll_timeout_atomic(efuse->base + MESON_MX_EFUSE_CNTL1, 1308caef1faSMartin Blumenstingl regval, 1318caef1faSMartin Blumenstingl (!(regval & MESON_MX_EFUSE_CNTL1_AUTO_RD_BUSY)), 1328caef1faSMartin Blumenstingl 1, 1000); 1338caef1faSMartin Blumenstingl if (err) { 1348caef1faSMartin Blumenstingl dev_err(efuse->config.dev, 1358caef1faSMartin Blumenstingl "Timeout while reading efuse address %u\n", addr); 1368caef1faSMartin Blumenstingl return err; 1378caef1faSMartin Blumenstingl } 1388caef1faSMartin Blumenstingl 1398caef1faSMartin Blumenstingl *value = readl(efuse->base + MESON_MX_EFUSE_CNTL2); 1408caef1faSMartin Blumenstingl 1418caef1faSMartin Blumenstingl return 0; 1428caef1faSMartin Blumenstingl } 1438caef1faSMartin Blumenstingl 1448caef1faSMartin Blumenstingl static int meson_mx_efuse_read(void *context, unsigned int offset, 1458caef1faSMartin Blumenstingl void *buf, size_t bytes) 1468caef1faSMartin Blumenstingl { 1478caef1faSMartin Blumenstingl struct meson_mx_efuse *efuse = context; 1488caef1faSMartin Blumenstingl u32 tmp; 1498caef1faSMartin Blumenstingl int err, i, addr; 1508caef1faSMartin Blumenstingl 1518caef1faSMartin Blumenstingl err = meson_mx_efuse_hw_enable(efuse); 1528caef1faSMartin Blumenstingl if (err) 1538caef1faSMartin Blumenstingl return err; 1548caef1faSMartin Blumenstingl 1558caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1568caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_ENABLE, 1578caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_ENABLE); 1588caef1faSMartin Blumenstingl 159*8a42d3fcSMartin Blumenstingl for (i = 0; i < bytes; i += efuse->config.word_size) { 160*8a42d3fcSMartin Blumenstingl addr = (offset + i) / efuse->config.word_size; 1618caef1faSMartin Blumenstingl 1628caef1faSMartin Blumenstingl err = meson_mx_efuse_read_addr(efuse, addr, &tmp); 1638caef1faSMartin Blumenstingl if (err) 1648caef1faSMartin Blumenstingl break; 1658caef1faSMartin Blumenstingl 1668caef1faSMartin Blumenstingl memcpy(buf + i, &tmp, efuse->config.word_size); 1678caef1faSMartin Blumenstingl } 1688caef1faSMartin Blumenstingl 1698caef1faSMartin Blumenstingl meson_mx_efuse_mask_bits(efuse, MESON_MX_EFUSE_CNTL1, 1708caef1faSMartin Blumenstingl MESON_MX_EFUSE_CNTL1_AUTO_RD_ENABLE, 0); 1718caef1faSMartin Blumenstingl 1728caef1faSMartin Blumenstingl meson_mx_efuse_hw_disable(efuse); 1738caef1faSMartin Blumenstingl 1748caef1faSMartin Blumenstingl return err; 1758caef1faSMartin Blumenstingl } 1768caef1faSMartin Blumenstingl 1778caef1faSMartin Blumenstingl static const struct meson_mx_efuse_platform_data meson6_efuse_data = { 1788caef1faSMartin Blumenstingl .name = "meson6-efuse", 1798caef1faSMartin Blumenstingl .word_size = 1, 1808caef1faSMartin Blumenstingl }; 1818caef1faSMartin Blumenstingl 1828caef1faSMartin Blumenstingl static const struct meson_mx_efuse_platform_data meson8_efuse_data = { 1838caef1faSMartin Blumenstingl .name = "meson8-efuse", 1848caef1faSMartin Blumenstingl .word_size = 4, 1858caef1faSMartin Blumenstingl }; 1868caef1faSMartin Blumenstingl 1878caef1faSMartin Blumenstingl static const struct meson_mx_efuse_platform_data meson8b_efuse_data = { 1888caef1faSMartin Blumenstingl .name = "meson8b-efuse", 1898caef1faSMartin Blumenstingl .word_size = 4, 1908caef1faSMartin Blumenstingl }; 1918caef1faSMartin Blumenstingl 1928caef1faSMartin Blumenstingl static const struct of_device_id meson_mx_efuse_match[] = { 1938caef1faSMartin Blumenstingl { .compatible = "amlogic,meson6-efuse", .data = &meson6_efuse_data }, 1948caef1faSMartin Blumenstingl { .compatible = "amlogic,meson8-efuse", .data = &meson8_efuse_data }, 1958caef1faSMartin Blumenstingl { .compatible = "amlogic,meson8b-efuse", .data = &meson8b_efuse_data }, 1968caef1faSMartin Blumenstingl { /* sentinel */ }, 1978caef1faSMartin Blumenstingl }; 1988caef1faSMartin Blumenstingl MODULE_DEVICE_TABLE(of, meson_mx_efuse_match); 1998caef1faSMartin Blumenstingl 2008caef1faSMartin Blumenstingl static int meson_mx_efuse_probe(struct platform_device *pdev) 2018caef1faSMartin Blumenstingl { 2028caef1faSMartin Blumenstingl const struct meson_mx_efuse_platform_data *drvdata; 2038caef1faSMartin Blumenstingl struct meson_mx_efuse *efuse; 2048caef1faSMartin Blumenstingl struct resource *res; 2058caef1faSMartin Blumenstingl 2068caef1faSMartin Blumenstingl drvdata = of_device_get_match_data(&pdev->dev); 2078caef1faSMartin Blumenstingl if (!drvdata) 2088caef1faSMartin Blumenstingl return -EINVAL; 2098caef1faSMartin Blumenstingl 2108caef1faSMartin Blumenstingl efuse = devm_kzalloc(&pdev->dev, sizeof(*efuse), GFP_KERNEL); 2118caef1faSMartin Blumenstingl if (!efuse) 2128caef1faSMartin Blumenstingl return -ENOMEM; 2138caef1faSMartin Blumenstingl 2148caef1faSMartin Blumenstingl res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 2158caef1faSMartin Blumenstingl efuse->base = devm_ioremap_resource(&pdev->dev, res); 2168caef1faSMartin Blumenstingl if (IS_ERR(efuse->base)) 2178caef1faSMartin Blumenstingl return PTR_ERR(efuse->base); 2188caef1faSMartin Blumenstingl 2198caef1faSMartin Blumenstingl efuse->config.name = devm_kstrdup(&pdev->dev, drvdata->name, 2208caef1faSMartin Blumenstingl GFP_KERNEL); 2218caef1faSMartin Blumenstingl efuse->config.owner = THIS_MODULE; 2228caef1faSMartin Blumenstingl efuse->config.dev = &pdev->dev; 2238caef1faSMartin Blumenstingl efuse->config.priv = efuse; 2248caef1faSMartin Blumenstingl efuse->config.stride = drvdata->word_size; 2258caef1faSMartin Blumenstingl efuse->config.word_size = drvdata->word_size; 2268caef1faSMartin Blumenstingl efuse->config.size = SZ_512; 2278caef1faSMartin Blumenstingl efuse->config.read_only = true; 2288caef1faSMartin Blumenstingl efuse->config.reg_read = meson_mx_efuse_read; 2298caef1faSMartin Blumenstingl 2308caef1faSMartin Blumenstingl efuse->core_clk = devm_clk_get(&pdev->dev, "core"); 2318caef1faSMartin Blumenstingl if (IS_ERR(efuse->core_clk)) { 2328caef1faSMartin Blumenstingl dev_err(&pdev->dev, "Failed to get core clock\n"); 2338caef1faSMartin Blumenstingl return PTR_ERR(efuse->core_clk); 2348caef1faSMartin Blumenstingl } 2358caef1faSMartin Blumenstingl 2368caef1faSMartin Blumenstingl efuse->nvmem = nvmem_register(&efuse->config); 2378caef1faSMartin Blumenstingl if (IS_ERR(efuse->nvmem)) 2388caef1faSMartin Blumenstingl return PTR_ERR(efuse->nvmem); 2398caef1faSMartin Blumenstingl 2408caef1faSMartin Blumenstingl platform_set_drvdata(pdev, efuse); 2418caef1faSMartin Blumenstingl 2428caef1faSMartin Blumenstingl return 0; 2438caef1faSMartin Blumenstingl } 2448caef1faSMartin Blumenstingl 2458caef1faSMartin Blumenstingl static int meson_mx_efuse_remove(struct platform_device *pdev) 2468caef1faSMartin Blumenstingl { 2478caef1faSMartin Blumenstingl struct meson_mx_efuse *efuse = platform_get_drvdata(pdev); 2488caef1faSMartin Blumenstingl 2498caef1faSMartin Blumenstingl return nvmem_unregister(efuse->nvmem); 2508caef1faSMartin Blumenstingl } 2518caef1faSMartin Blumenstingl 2528caef1faSMartin Blumenstingl static struct platform_driver meson_mx_efuse_driver = { 2538caef1faSMartin Blumenstingl .probe = meson_mx_efuse_probe, 2548caef1faSMartin Blumenstingl .remove = meson_mx_efuse_remove, 2558caef1faSMartin Blumenstingl .driver = { 2568caef1faSMartin Blumenstingl .name = "meson-mx-efuse", 2578caef1faSMartin Blumenstingl .of_match_table = meson_mx_efuse_match, 2588caef1faSMartin Blumenstingl }, 2598caef1faSMartin Blumenstingl }; 2608caef1faSMartin Blumenstingl 2618caef1faSMartin Blumenstingl module_platform_driver(meson_mx_efuse_driver); 2628caef1faSMartin Blumenstingl 2638caef1faSMartin Blumenstingl MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>"); 2648caef1faSMartin Blumenstingl MODULE_DESCRIPTION("Amlogic Meson MX eFuse NVMEM driver"); 2658caef1faSMartin Blumenstingl MODULE_LICENSE("GPL v2"); 266