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-rw-r--r--arch/avr32/mach-at32ap/hsmc.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/arch/avr32/mach-at32ap/hsmc.c b/arch/avr32/mach-at32ap/hsmc.c
new file mode 100644
index 000000000000..7691721928a7
--- /dev/null
+++ b/arch/avr32/mach-at32ap/hsmc.c
@@ -0,0 +1,164 @@
1/*
2 * Static Memory Controller for AT32 chips
3 *
4 * Copyright (C) 2006 Atmel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#define DEBUG
11#include <linux/clk.h>
12#include <linux/err.h>
13#include <linux/init.h>
14#include <linux/module.h>
15#include <linux/platform_device.h>
16
17#include <asm/io.h>
18#include <asm/arch/smc.h>
19
20#include "hsmc.h"
21
22#define NR_CHIP_SELECTS 6
23
24struct hsmc {
25 void __iomem *regs;
26 struct clk *pclk;
27 struct clk *mck;
28};
29
30static struct hsmc *hsmc;
31
32int smc_set_configuration(int cs, const struct smc_config *config)
33{
34 unsigned long mul;
35 unsigned long offset;
36 u32 setup, pulse, cycle, mode;
37
38 if (!hsmc)
39 return -ENODEV;
40 if (cs >= NR_CHIP_SELECTS)
41 return -EINVAL;
42
43 /*
44 * cycles = x / T = x * f
45 * = ((x * 1000000000) * ((f * 65536) / 1000000000)) / 65536
46 * = ((x * 1000000000) * (((f / 10000) * 65536) / 100000)) / 65536
47 */
48 mul = (clk_get_rate(hsmc->mck) / 10000) << 16;
49 mul /= 100000;
50
51#define ns2cyc(x) ((((x) * mul) + 65535) >> 16)
52
53 setup = (HSMC_BF(NWE_SETUP, ns2cyc(config->nwe_setup))
54 | HSMC_BF(NCS_WR_SETUP, ns2cyc(config->ncs_write_setup))
55 | HSMC_BF(NRD_SETUP, ns2cyc(config->nrd_setup))
56 | HSMC_BF(NCS_RD_SETUP, ns2cyc(config->ncs_read_setup)));
57 pulse = (HSMC_BF(NWE_PULSE, ns2cyc(config->nwe_pulse))
58 | HSMC_BF(NCS_WR_PULSE, ns2cyc(config->ncs_write_pulse))
59 | HSMC_BF(NRD_PULSE, ns2cyc(config->nrd_pulse))
60 | HSMC_BF(NCS_RD_PULSE, ns2cyc(config->ncs_read_pulse)));
61 cycle = (HSMC_BF(NWE_CYCLE, ns2cyc(config->write_cycle))
62 | HSMC_BF(NRD_CYCLE, ns2cyc(config->read_cycle)));
63
64 switch (config->bus_width) {
65 case 1:
66 mode = HSMC_BF(DBW, HSMC_DBW_8_BITS);
67 break;
68 case 2:
69 mode = HSMC_BF(DBW, HSMC_DBW_16_BITS);
70 break;
71 case 4:
72 mode = HSMC_BF(DBW, HSMC_DBW_32_BITS);
73 break;
74 default:
75 return -EINVAL;
76 }
77
78 if (config->nrd_controlled)
79 mode |= HSMC_BIT(READ_MODE);
80 if (config->nwe_controlled)
81 mode |= HSMC_BIT(WRITE_MODE);
82 if (config->byte_write)
83 mode |= HSMC_BIT(BAT);
84
85 pr_debug("smc cs%d: setup/%08x pulse/%08x cycle/%08x mode/%08x\n",
86 cs, setup, pulse, cycle, mode);
87
88 offset = cs * 0x10;
89 hsmc_writel(hsmc, SETUP0 + offset, setup);
90 hsmc_writel(hsmc, PULSE0 + offset, pulse);
91 hsmc_writel(hsmc, CYCLE0 + offset, cycle);
92 hsmc_writel(hsmc, MODE0 + offset, mode);
93 hsmc_readl(hsmc, MODE0); /* I/O barrier */
94
95 return 0;
96}
97EXPORT_SYMBOL(smc_set_configuration);
98
99static int hsmc_probe(struct platform_device *pdev)
100{
101 struct resource *regs;
102 struct clk *pclk, *mck;
103 int ret;
104
105 if (hsmc)
106 return -EBUSY;
107
108 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
109 if (!regs)
110 return -ENXIO;
111 pclk = clk_get(&pdev->dev, "pclk");
112 if (IS_ERR(pclk))
113 return PTR_ERR(pclk);
114 mck = clk_get(&pdev->dev, "mck");
115 if (IS_ERR(mck)) {
116 ret = PTR_ERR(mck);
117 goto out_put_pclk;
118 }
119
120 ret = -ENOMEM;
121 hsmc = kzalloc(sizeof(struct hsmc), GFP_KERNEL);
122 if (!hsmc)
123 goto out_put_clocks;
124
125 clk_enable(pclk);
126 clk_enable(mck);
127
128 hsmc->pclk = pclk;
129 hsmc->mck = mck;
130 hsmc->regs = ioremap(regs->start, regs->end - regs->start + 1);
131 if (!hsmc->regs)
132 goto out_disable_clocks;
133
134 dev_info(&pdev->dev, "Atmel Static Memory Controller at 0x%08lx\n",
135 (unsigned long)regs->start);
136
137 platform_set_drvdata(pdev, hsmc);
138
139 return 0;
140
141out_disable_clocks:
142 clk_disable(mck);
143 clk_disable(pclk);
144 kfree(hsmc);
145out_put_clocks:
146 clk_put(mck);
147out_put_pclk:
148 clk_put(pclk);
149 hsmc = NULL;
150 return ret;
151}
152
153static struct platform_driver hsmc_driver = {
154 .probe = hsmc_probe,
155 .driver = {
156 .name = "smc",
157 },
158};
159
160static int __init hsmc_init(void)
161{
162 return platform_driver_register(&hsmc_driver);
163}
164arch_initcall(hsmc_init);