drivers/soc/mediatek/mtk-infracfg.c

   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 }