16a624a9c8
This adds support for some miscellaneous bits of the infracfg controller. The mtk_infracfg_set/clear_bus_protection functions are necessary for the scpsys power domain driver to handle the bus protection bits which are contained in the infacfg register space. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Daniel Kurtz <djkurtz@chromium.org> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
92 lines
2.2 KiB
C
92 lines
2.2 KiB
C
/*
|
|
* Copyright (c) 2015 Pengutronix, Sascha Hauer <kernel@pengutronix.de>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <linux/export.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/soc/mediatek/infracfg.h>
|
|
#include <asm/processor.h>
|
|
|
|
#define INFRA_TOPAXI_PROTECTEN 0x0220
|
|
#define INFRA_TOPAXI_PROTECTSTA1 0x0228
|
|
|
|
/**
|
|
* mtk_infracfg_set_bus_protection - enable bus protection
|
|
* @regmap: The infracfg regmap
|
|
* @mask: The mask containing the protection bits to be enabled.
|
|
*
|
|
* This function enables the bus protection bits for disabled power
|
|
* domains so that the system does not hang when some unit accesses the
|
|
* bus while in power down.
|
|
*/
|
|
int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask)
|
|
{
|
|
unsigned long expired;
|
|
u32 val;
|
|
int ret;
|
|
|
|
regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, mask);
|
|
|
|
expired = jiffies + HZ;
|
|
|
|
while (1) {
|
|
ret = regmap_read(infracfg, INFRA_TOPAXI_PROTECTSTA1, &val);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if ((val & mask) == mask)
|
|
break;
|
|
|
|
cpu_relax();
|
|
if (time_after(jiffies, expired))
|
|
return -EIO;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mtk_infracfg_clear_bus_protection - disable bus protection
|
|
* @regmap: The infracfg regmap
|
|
* @mask: The mask containing the protection bits to be disabled.
|
|
*
|
|
* This function disables the bus protection bits previously enabled with
|
|
* mtk_infracfg_set_bus_protection.
|
|
*/
|
|
int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask)
|
|
{
|
|
unsigned long expired;
|
|
int ret;
|
|
|
|
regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0);
|
|
|
|
expired = jiffies + HZ;
|
|
|
|
while (1) {
|
|
u32 val;
|
|
|
|
ret = regmap_read(infracfg, INFRA_TOPAXI_PROTECTSTA1, &val);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (!(val & mask))
|
|
break;
|
|
|
|
cpu_relax();
|
|
if (time_after(jiffies, expired))
|
|
return -EIO;
|
|
}
|
|
|
|
return 0;
|
|
}
|