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 /** 16 * mtk_infracfg_set_bus_protection - enable bus protection 17 * @infracfg: The infracfg regmap 18 * @mask: The mask containing the protection bits to be enabled. 19 * @reg_update: The boolean flag determines to set the protection bits 20 * by regmap_update_bits with enable register(PROTECTEN) or 21 * by regmap_write with set register(PROTECTEN_SET). 22 * 23 * This function enables the bus protection bits for disabled power 24 * domains so that the system does not hang when some unit accesses the 25 * bus while in power down. 26 */ 27 int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask, 28 bool reg_update) 29 { 30 u32 val; 31 int ret; 32 33 if (reg_update) 34 regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 35 mask); 36 else 37 regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_SET, mask); 38 39 ret = regmap_read_poll_timeout(infracfg, INFRA_TOPAXI_PROTECTSTA1, 40 val, (val & mask) == mask, 41 MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); 42 43 return ret; 44 } 45 46 /** 47 * mtk_infracfg_clear_bus_protection - disable bus protection 48 * @infracfg: The infracfg regmap 49 * @mask: The mask containing the protection bits to be disabled. 50 * @reg_update: The boolean flag determines to clear the protection bits 51 * by regmap_update_bits with enable register(PROTECTEN) or 52 * by regmap_write with clear register(PROTECTEN_CLR). 53 * 54 * This function disables the bus protection bits previously enabled with 55 * mtk_infracfg_set_bus_protection. 56 */ 57 58 int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask, 59 bool reg_update) 60 { 61 int ret; 62 u32 val; 63 64 if (reg_update) 65 regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0); 66 else 67 regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_CLR, mask); 68 69 ret = regmap_read_poll_timeout(infracfg, INFRA_TOPAXI_PROTECTSTA1, 70 val, !(val & mask), 71 MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT); 72 73 return ret; 74 } 75