1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2015 Pengutronix, Sascha Hauer <kernel@pengutronix.de> 4 */ 5 6 #include <linux/export.h> 7 #include <linux/jiffies.h> 8 #include <linux/regmap.h> 9 #include <linux/soc/mediatek/infracfg.h> 10 #include <asm/processor.h> 11 12 #define MTK_POLL_DELAY_US 10 13 #define MTK_POLL_TIMEOUT (jiffies_to_usecs(HZ)) 14 15 #define INFRA_TOPAXI_PROTECTEN 0x0220 16 #define INFRA_TOPAXI_PROTECTSTA1 0x0228 17 #define INFRA_TOPAXI_PROTECTEN_SET 0x0260 18 #define INFRA_TOPAXI_PROTECTEN_CLR 0x0264 19 20 /** 21 * mtk_infracfg_set_bus_protection - enable bus protection 22 * @regmap: The infracfg regmap 23 * @mask: The mask containing the protection bits to be enabled. 24 * @reg_update: The boolean flag determines to set the protection bits 25 * by regmap_update_bits with enable register(PROTECTEN) or 26 * by regmap_write with set register(PROTECTEN_SET). 27 * 28 * This function enables the bus protection bits for disabled power 29 * domains so that the system does not hang when some unit accesses the 30 * bus while in power down. 31 */ 32 int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask, 33 bool reg_update) 34 { 35 u32 val; 36 int ret; 37 38 if (reg_update) 39 regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 40 mask); 41 else 42 regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_SET, mask); 43 44 ret = regmap_read_poll_timeout(infracfg, INFRA_TOPAXI_PROTECTSTA1, 45 val, (val & mask) == mask, 46 MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); 47 48 return ret; 49 } 50 51 /** 52 * mtk_infracfg_clear_bus_protection - disable bus protection 53 * @regmap: The infracfg regmap 54 * @mask: The mask containing the protection bits to be disabled. 55 * @reg_update: The boolean flag determines to clear the protection bits 56 * by regmap_update_bits with enable register(PROTECTEN) or 57 * by regmap_write with clear register(PROTECTEN_CLR). 58 * 59 * This function disables the bus protection bits previously enabled with 60 * mtk_infracfg_set_bus_protection. 61 */ 62 63 int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask, 64 bool reg_update) 65 { 66 int ret; 67 u32 val; 68 69 if (reg_update) 70 regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0); 71 else 72 regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_CLR, mask); 73 74 ret = regmap_read_poll_timeout(infracfg, INFRA_TOPAXI_PROTECTSTA1, 75 val, !(val & mask), 76 MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); 77 78 return ret; 79 } 80