xref: /openbmc/linux/arch/arm/mach-omap1/sram-init.c (revision 2169e6da)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP SRAM detection and management
4  *
5  * Copyright (C) 2005 Nokia Corporation
6  * Written by Tony Lindgren <tony@atomide.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/io.h>
13 
14 #include <asm/fncpy.h>
15 #include <asm/tlb.h>
16 #include <asm/cacheflush.h>
17 
18 #include <asm/mach/map.h>
19 
20 #include "soc.h"
21 #include "sram.h"
22 
23 #define OMAP1_SRAM_PA		0x20000000
24 #define SRAM_BOOTLOADER_SZ	0x80
25 
26 /*
27  * The amount of SRAM depends on the core type.
28  * Note that we cannot try to test for SRAM here because writes
29  * to secure SRAM will hang the system. Also the SRAM is not
30  * yet mapped at this point.
31  */
32 static void __init omap_detect_and_map_sram(void)
33 {
34 	unsigned long omap_sram_skip = SRAM_BOOTLOADER_SZ;
35 	unsigned long omap_sram_start = OMAP1_SRAM_PA;
36 	unsigned long omap_sram_size;
37 
38 	if (cpu_is_omap7xx())
39 		omap_sram_size = 0x32000;	/* 200K */
40 	else if (cpu_is_omap15xx())
41 		omap_sram_size = 0x30000;	/* 192K */
42 	else if (cpu_is_omap1610() || cpu_is_omap1611() ||
43 			cpu_is_omap1621() || cpu_is_omap1710())
44 		omap_sram_size = 0x4000;	/* 16K */
45 	else {
46 		pr_err("Could not detect SRAM size\n");
47 		omap_sram_size = 0x4000;
48 	}
49 
50 	omap_map_sram(omap_sram_start, omap_sram_size,
51 		omap_sram_skip, 1);
52 }
53 
54 static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
55 
56 void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
57 {
58 	BUG_ON(!_omap_sram_reprogram_clock);
59 	/* On 730, bit 13 must always be 1 */
60 	if (cpu_is_omap7xx())
61 		ckctl |= 0x2000;
62 	_omap_sram_reprogram_clock(dpllctl, ckctl);
63 }
64 
65 int __init omap_sram_init(void)
66 {
67 	omap_detect_and_map_sram();
68 	_omap_sram_reprogram_clock =
69 			omap_sram_push(omap1_sram_reprogram_clock,
70 					omap1_sram_reprogram_clock_sz);
71 
72 	return 0;
73 }
74