xref: /openbmc/linux/arch/arm/mach-lpc32xx/common.c (revision bb3982b4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * arch/arm/mach-lpc32xx/common.c
4  *
5  * Author: Kevin Wells <kevin.wells@nxp.com>
6  *
7  * Copyright (C) 2010 NXP Semiconductors
8  */
9 
10 #include <linux/init.h>
11 
12 #include <asm/mach/map.h>
13 #include <asm/system_info.h>
14 
15 #include <mach/hardware.h>
16 #include <mach/platform.h>
17 #include "common.h"
18 
19 /*
20  * Returns the unique ID for the device
21  */
22 void lpc32xx_get_uid(u32 devid[4])
23 {
24 	int i;
25 
26 	for (i = 0; i < 4; i++)
27 		devid[i] = __raw_readl(LPC32XX_CLKPWR_DEVID(i << 2));
28 }
29 
30 /*
31  * Detects and returns IRAM size for the device variation
32  */
33 #define LPC32XX_IRAM_BANK_SIZE SZ_128K
34 static u32 iram_size;
35 u32 lpc32xx_return_iram_size(void)
36 {
37 	if (iram_size == 0) {
38 		u32 savedval1, savedval2;
39 		void __iomem *iramptr1, *iramptr2;
40 
41 		iramptr1 = io_p2v(LPC32XX_IRAM_BASE);
42 		iramptr2 = io_p2v(LPC32XX_IRAM_BASE + LPC32XX_IRAM_BANK_SIZE);
43 		savedval1 = __raw_readl(iramptr1);
44 		savedval2 = __raw_readl(iramptr2);
45 
46 		if (savedval1 == savedval2) {
47 			__raw_writel(savedval2 + 1, iramptr2);
48 			if (__raw_readl(iramptr1) == savedval2 + 1)
49 				iram_size = LPC32XX_IRAM_BANK_SIZE;
50 			else
51 				iram_size = LPC32XX_IRAM_BANK_SIZE * 2;
52 			__raw_writel(savedval2, iramptr2);
53 		} else
54 			iram_size = LPC32XX_IRAM_BANK_SIZE * 2;
55 	}
56 
57 	return iram_size;
58 }
59 EXPORT_SYMBOL_GPL(lpc32xx_return_iram_size);
60 
61 static struct map_desc lpc32xx_io_desc[] __initdata = {
62 	{
63 		.virtual	= (unsigned long)IO_ADDRESS(LPC32XX_AHB0_START),
64 		.pfn		= __phys_to_pfn(LPC32XX_AHB0_START),
65 		.length		= LPC32XX_AHB0_SIZE,
66 		.type		= MT_DEVICE
67 	},
68 	{
69 		.virtual	= (unsigned long)IO_ADDRESS(LPC32XX_AHB1_START),
70 		.pfn		= __phys_to_pfn(LPC32XX_AHB1_START),
71 		.length		= LPC32XX_AHB1_SIZE,
72 		.type		= MT_DEVICE
73 	},
74 	{
75 		.virtual	= (unsigned long)IO_ADDRESS(LPC32XX_FABAPB_START),
76 		.pfn		= __phys_to_pfn(LPC32XX_FABAPB_START),
77 		.length		= LPC32XX_FABAPB_SIZE,
78 		.type		= MT_DEVICE
79 	},
80 	{
81 		.virtual	= (unsigned long)IO_ADDRESS(LPC32XX_IRAM_BASE),
82 		.pfn		= __phys_to_pfn(LPC32XX_IRAM_BASE),
83 		.length		= (LPC32XX_IRAM_BANK_SIZE * 2),
84 		.type		= MT_DEVICE
85 	},
86 };
87 
88 void __init lpc32xx_map_io(void)
89 {
90 	iotable_init(lpc32xx_io_desc, ARRAY_SIZE(lpc32xx_io_desc));
91 }
92 
93 static int __init lpc32xx_check_uid(void)
94 {
95 	u32 uid[4];
96 
97 	lpc32xx_get_uid(uid);
98 
99 	printk(KERN_INFO "LPC32XX unique ID: %08x%08x%08x%08x\n",
100 		uid[3], uid[2], uid[1], uid[0]);
101 
102 	if (!system_serial_low && !system_serial_high) {
103 		system_serial_low = uid[0];
104 		system_serial_high = uid[1];
105 	}
106 
107 	return 1;
108 }
109 arch_initcall(lpc32xx_check_uid);
110