LXR linux/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/**
  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 */
  27int 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
  58int 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