1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * SMS/SDRC (SDRAM controller) common code for OMAP2/3
4 *
5 * Copyright (C) 2005, 2008 Texas Instruments Inc.
6 * Copyright (C) 2005, 2008 Nokia Corporation
7 *
8 * Tony Lindgren <tony@atomide.com>
9 * Paul Walmsley
10 * Richard Woodruff <r-woodruff2@ti.com>
11 */
12 #undef DEBUG
13
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/device.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/delay.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22
23 #include "common.h"
24 #include "clock.h"
25 #include "sdrc.h"
26
27 static struct omap_sdrc_params *sdrc_init_params_cs0, *sdrc_init_params_cs1;
28
29 void __iomem *omap2_sdrc_base;
30 void __iomem *omap2_sms_base;
31
32 struct omap2_sms_regs {
33 u32 sms_sysconfig;
34 };
35
36 static struct omap2_sms_regs sms_context;
37
38 /* SDRC_POWER register bits */
39 #define SDRC_POWER_EXTCLKDIS_SHIFT 3
40 #define SDRC_POWER_PWDENA_SHIFT 2
41 #define SDRC_POWER_PAGEPOLICY_SHIFT 0
42
43 /**
44 * omap2_sms_save_context - Save SMS registers
45 *
46 * Save SMS registers that need to be restored after off mode.
47 */
48 static void omap2_sms_save_context(void)
49 {
50 sms_context.sms_sysconfig = sms_read_reg(SMS_SYSCONFIG);
51 }
52
53 /**
54 * omap2_sms_restore_context - Restore SMS registers
55 *
56 * Restore SMS registers that need to be Restored after off mode.
57 */
58 void omap2_sms_restore_context(void)
59 {
60 sms_write_reg(sms_context.sms_sysconfig, SMS_SYSCONFIG);
61 }
62
63 void __init omap2_set_globals_sdrc(void __iomem *sdrc, void __iomem *sms)
64 {
65 omap2_sdrc_base = sdrc;
66 omap2_sms_base = sms;
67 }
68
69 /**
70 * omap2_sdrc_init - initialize SMS, SDRC devices on boot
71 * @sdrc_cs[01]: pointers to a null-terminated list of struct omap_sdrc_params
72 * Support for 2 chip selects timings
73 *
74 * Turn on smart idle modes for SDRAM scheduler and controller.
75 * Program a known-good configuration for the SDRC to deal with buggy
76 * bootloaders.
77 */
78 void __init omap2_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
79 struct omap_sdrc_params *sdrc_cs1)
80 {
81 u32 l;
82
83 l = sms_read_reg(SMS_SYSCONFIG);
84 l &= ~(0x3 << 3);
85 l |= (0x2 << 3);
86 sms_write_reg(l, SMS_SYSCONFIG);
87
88 l = sdrc_read_reg(SDRC_SYSCONFIG);
89 l &= ~(0x3 << 3);
90 l |= (0x2 << 3);
91 sdrc_write_reg(l, SDRC_SYSCONFIG);
92
93 sdrc_init_params_cs0 = sdrc_cs0;
94 sdrc_init_params_cs1 = sdrc_cs1;
95
96 /* XXX Enable SRFRONIDLEREQ here also? */
97 /*
98 * PWDENA should not be set due to 34xx erratum 1.150 - PWDENA
99 * can cause random memory corruption
100 */
101 l = (1 << SDRC_POWER_EXTCLKDIS_SHIFT) |
102 (1 << SDRC_POWER_PAGEPOLICY_SHIFT);
103 sdrc_write_reg(l, SDRC_POWER);
104 omap2_sms_save_context();
105 }
106
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