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 }