1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
/*
* linux/arch/arm/plat-omap/sram.c
*
* OMAP SRAM detection and management
*
* Copyright (C) 2005 Nokia Corporation
* Written by Tony Lindgren <tony@atomide.com>
*
* Copyright (C) 2009-2012 Texas Instruments
* Added OMAP4/5 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* 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.
*/
#undef DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <asm/fncpy.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>
#include <asm/set_memory.h>
#include <asm/mach/map.h>
#include <plat/sram.h>
#define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1)))
static void __iomem *omap_sram_base;
static unsigned long omap_sram_skip;
static unsigned long omap_sram_size;
static void __iomem *omap_sram_ceil;
/*
* Memory allocator for SRAM: calculates the new ceiling address
* for pushing a function using the fncpy API.
*
* Note that fncpy requires the returned address to be aligned
* to an 8-byte boundary.
*/
static void *omap_sram_push_address(unsigned long size)
{
unsigned long available, new_ceil = (unsigned long)omap_sram_ceil;
available = omap_sram_ceil - (omap_sram_base + omap_sram_skip);
if (size > available) {
pr_err("Not enough space in SRAM\n");
return NULL;
}
new_ceil -= size;
new_ceil = ROUND_DOWN(new_ceil, FNCPY_ALIGN);
omap_sram_ceil = IOMEM(new_ceil);
return (void *)omap_sram_ceil;
}
void *omap_sram_push(void *funcp, unsigned long size)
{
void *sram;
unsigned long base;
int pages;
void *dst = NULL;
sram = omap_sram_push_address(size);
if (!sram)
return NULL;
base = (unsigned long)sram & PAGE_MASK;
pages = PAGE_ALIGN(size) / PAGE_SIZE;
set_memory_rw(base, pages);
dst = fncpy(sram, funcp, size);
set_memory_ro(base, pages);
set_memory_x(base, pages);
return dst;
}
/*
* The SRAM context is lost during off-idle and stack
* needs to be reset.
*/
void omap_sram_reset(void)
{
omap_sram_ceil = omap_sram_base + omap_sram_size;
}
/*
* Note that we cannot use ioremap for SRAM, as clock init needs SRAM early.
*/
void __init omap_map_sram(unsigned long start, unsigned long size,
unsigned long skip, int cached)
{
unsigned long base;
int pages;
if (size == 0)
return;
start = ROUND_DOWN(start, PAGE_SIZE);
omap_sram_size = size;
omap_sram_skip = skip;
omap_sram_base = __arm_ioremap_exec(start, size, cached);
if (!omap_sram_base) {
pr_err("SRAM: Could not map\n");
return;
}
omap_sram_reset();
/*
* Looks like we need to preserve some bootloader code at the
* beginning of SRAM for jumping to flash for reboot to work...
*/
memset_io(omap_sram_base + omap_sram_skip, 0,
omap_sram_size - omap_sram_skip);
base = (unsigned long)omap_sram_base;
pages = PAGE_ALIGN(omap_sram_size) / PAGE_SIZE;
set_memory_ro(base, pages);
set_memory_x(base, pages);
}
|