1 /*
2  * Broadcom BCM63xx Processor Monitor Bus shared routines (SMP and reset)
3  *
4  * Copyright (C) 2015, Broadcom Corporation
5  * Author: Florian Fainelli <f.fainelli@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation version 2.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 #ifndef __BCM63XX_PMB_H
17 #define __BCM63XX_PMB_H
18 
19 #include <linux/io.h>
20 #include <linux/types.h>
21 #include <linux/delay.h>
22 #include <linux/err.h>
23 
24 /* PMB Master controller register */
25 #define PMB_CTRL		0x00
26 #define  PMC_PMBM_START		(1 << 31)
27 #define  PMC_PMBM_TIMEOUT	(1 << 30)
28 #define  PMC_PMBM_SLAVE_ERR	(1 << 29)
29 #define  PMC_PMBM_BUSY		(1 << 28)
30 #define  PMC_PMBM_READ		(0 << 20)
31 #define  PMC_PMBM_WRITE		(1 << 20)
32 #define PMB_WR_DATA		0x04
33 #define PMB_TIMEOUT		0x08
34 #define PMB_RD_DATA		0x0C
35 
36 #define PMB_BUS_ID_SHIFT	8
37 
38 /* Perform the low-level PMB master operation, shared between reads and
39  * writes.
40  */
__bpcm_do_op(void __iomem * master,unsigned int addr,u32 off,u32 op)41 static inline int __bpcm_do_op(void __iomem *master, unsigned int addr,
42 			       u32 off, u32 op)
43 {
44 	unsigned int timeout = 1000;
45 	u32 cmd;
46 
47 	cmd = (PMC_PMBM_START | op | (addr & 0xff) << 12 | off);
48 	writel(cmd, master + PMB_CTRL);
49 	do {
50 		cmd = readl(master + PMB_CTRL);
51 		if (!(cmd & PMC_PMBM_START))
52 			return 0;
53 
54 		if (cmd & PMC_PMBM_SLAVE_ERR)
55 			return -EIO;
56 
57 		if (cmd & PMC_PMBM_TIMEOUT)
58 			return -ETIMEDOUT;
59 
60 		udelay(1);
61 	} while (timeout-- > 0);
62 
63 	return -ETIMEDOUT;
64 }
65 
bpcm_rd(void __iomem * master,unsigned int addr,u32 off,u32 * val)66 static inline int bpcm_rd(void __iomem *master, unsigned int addr,
67 			  u32 off, u32 *val)
68 {
69 	int ret = 0;
70 
71 	ret = __bpcm_do_op(master, addr, off >> 2, PMC_PMBM_READ);
72 	*val = readl(master + PMB_RD_DATA);
73 
74 	return ret;
75 }
76 
bpcm_wr(void __iomem * master,unsigned int addr,u32 off,u32 val)77 static inline int bpcm_wr(void __iomem *master, unsigned int addr,
78 			  u32 off, u32 val)
79 {
80 	int ret = 0;
81 
82 	writel(val, master + PMB_WR_DATA);
83 	ret = __bpcm_do_op(master, addr, off >> 2, PMC_PMBM_WRITE);
84 
85 	return ret;
86 }
87 
88 #endif /* __BCM63XX_PMB_H */
89