Commit | Line | Data |
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09ec1d7e | 1 | /* |
ccae941e | 2 | * Copyright (c) 2006-2008 Simtec Electronics |
140780ab BD |
3 | * http://armlinux.simtec.co.uk/ |
4 | * Ben Dooks <ben@simtec.co.uk> | |
5 | * | |
6 | * S3C2412/S3C2443 (PL093 based) IO timing support | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | */ | |
12 | ||
13 | #include <linux/init.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <linux/ioport.h> | |
17 | #include <linux/cpufreq.h> | |
e6d197a6 | 18 | #include <linux/seq_file.h> |
edbaa603 | 19 | #include <linux/device.h> |
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20 | #include <linux/delay.h> |
21 | #include <linux/clk.h> | |
22 | #include <linux/err.h> | |
5a0e3ad6 | 23 | #include <linux/slab.h> |
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24 | |
25 | #include <linux/amba/pl093.h> | |
26 | ||
27 | #include <asm/mach/arch.h> | |
28 | #include <asm/mach/map.h> | |
29 | ||
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30 | #include <plat/cpu.h> |
31 | #include <plat/cpu-freq-core.h> | |
140780ab | 32 | |
f023f8dd | 33 | #include <mach/s3c2412.h> |
d3c01e7e | 34 | |
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35 | #define print_ns(x) ((x) / 10), ((x) % 10) |
36 | ||
37 | /** | |
38 | * s3c2412_print_timing - print timing infromation via printk. | |
39 | * @pfx: The prefix to print each line with. | |
40 | * @iot: The IO timing information | |
41 | */ | |
42 | static void s3c2412_print_timing(const char *pfx, struct s3c_iotimings *iot) | |
43 | { | |
44 | struct s3c2412_iobank_timing *bt; | |
45 | unsigned int bank; | |
46 | ||
47 | for (bank = 0; bank < MAX_BANKS; bank++) { | |
48 | bt = iot->bank[bank].io_2412; | |
49 | if (!bt) | |
50 | continue; | |
51 | ||
52 | printk(KERN_DEBUG "%s: %d: idcy=%d.%d wstrd=%d.%d wstwr=%d,%d" | |
53 | "wstoen=%d.%d wstwen=%d.%d wstbrd=%d.%d\n", pfx, bank, | |
54 | print_ns(bt->idcy), | |
55 | print_ns(bt->wstrd), | |
56 | print_ns(bt->wstwr), | |
57 | print_ns(bt->wstoen), | |
58 | print_ns(bt->wstwen), | |
59 | print_ns(bt->wstbrd)); | |
60 | } | |
61 | } | |
62 | ||
63 | /** | |
64 | * to_div - turn a cycle length into a divisor setting. | |
65 | * @cyc_tns: The cycle time in 10ths of nanoseconds. | |
66 | * @clk_tns: The clock period in 10ths of nanoseconds. | |
67 | */ | |
68 | static inline unsigned int to_div(unsigned int cyc_tns, unsigned int clk_tns) | |
69 | { | |
70 | return cyc_tns ? DIV_ROUND_UP(cyc_tns, clk_tns) : 0; | |
71 | } | |
72 | ||
73 | /** | |
74 | * calc_timing - calculate timing divisor value and check in range. | |
75 | * @hwtm: The hardware timing in 10ths of nanoseconds. | |
76 | * @clk_tns: The clock period in 10ths of nanoseconds. | |
77 | * @err: Pointer to err variable to update in event of failure. | |
78 | */ | |
79 | static unsigned int calc_timing(unsigned int hwtm, unsigned int clk_tns, | |
80 | unsigned int *err) | |
81 | { | |
82 | unsigned int ret = to_div(hwtm, clk_tns); | |
83 | ||
84 | if (ret > 0xf) | |
85 | *err = -EINVAL; | |
86 | ||
87 | return ret; | |
88 | } | |
89 | ||
90 | /** | |
91 | * s3c2412_calc_bank - calculate the bank divisor settings. | |
92 | * @cfg: The current frequency configuration. | |
93 | * @bt: The bank timing. | |
94 | */ | |
95 | static int s3c2412_calc_bank(struct s3c_cpufreq_config *cfg, | |
96 | struct s3c2412_iobank_timing *bt) | |
97 | { | |
98 | unsigned int hclk = cfg->freq.hclk_tns; | |
99 | int err = 0; | |
100 | ||
101 | bt->smbidcyr = calc_timing(bt->idcy, hclk, &err); | |
102 | bt->smbwstrd = calc_timing(bt->wstrd, hclk, &err); | |
103 | bt->smbwstwr = calc_timing(bt->wstwr, hclk, &err); | |
104 | bt->smbwstoen = calc_timing(bt->wstoen, hclk, &err); | |
105 | bt->smbwstwen = calc_timing(bt->wstwen, hclk, &err); | |
106 | bt->smbwstbrd = calc_timing(bt->wstbrd, hclk, &err); | |
107 | ||
108 | return err; | |
109 | } | |
110 | ||
e6d197a6 BD |
111 | /** |
112 | * s3c2412_iotiming_debugfs - debugfs show io bank timing information | |
113 | * @seq: The seq_file to write output to using seq_printf(). | |
114 | * @cfg: The current configuration. | |
115 | * @iob: The IO bank information to decode. | |
116 | */ | |
117 | void s3c2412_iotiming_debugfs(struct seq_file *seq, | |
118 | struct s3c_cpufreq_config *cfg, | |
119 | union s3c_iobank *iob) | |
120 | { | |
121 | struct s3c2412_iobank_timing *bt = iob->io_2412; | |
122 | ||
123 | seq_printf(seq, | |
124 | "\tRead: idcy=%d.%d wstrd=%d.%d wstwr=%d,%d" | |
125 | "wstoen=%d.%d wstwen=%d.%d wstbrd=%d.%d\n", | |
126 | print_ns(bt->idcy), | |
127 | print_ns(bt->wstrd), | |
128 | print_ns(bt->wstwr), | |
129 | print_ns(bt->wstoen), | |
130 | print_ns(bt->wstwen), | |
131 | print_ns(bt->wstbrd)); | |
132 | } | |
133 | ||
140780ab BD |
134 | /** |
135 | * s3c2412_iotiming_calc - calculate all the bank divisor settings. | |
136 | * @cfg: The current frequency configuration. | |
137 | * @iot: The bank timing information. | |
138 | * | |
139 | * Calculate the timing information for all the banks that are | |
140 | * configured as IO, using s3c2412_calc_bank(). | |
141 | */ | |
142 | int s3c2412_iotiming_calc(struct s3c_cpufreq_config *cfg, | |
143 | struct s3c_iotimings *iot) | |
144 | { | |
145 | struct s3c2412_iobank_timing *bt; | |
146 | int bank; | |
147 | int ret; | |
148 | ||
149 | for (bank = 0; bank < MAX_BANKS; bank++) { | |
150 | bt = iot->bank[bank].io_2412; | |
151 | if (!bt) | |
152 | continue; | |
153 | ||
154 | ret = s3c2412_calc_bank(cfg, bt); | |
155 | if (ret) { | |
156 | printk(KERN_ERR "%s: cannot calculate bank %d io\n", | |
157 | __func__, bank); | |
158 | goto err; | |
159 | } | |
160 | } | |
161 | ||
162 | return 0; | |
163 | err: | |
164 | return ret; | |
165 | } | |
166 | ||
167 | /** | |
168 | * s3c2412_iotiming_set - set the timing information | |
169 | * @cfg: The current frequency configuration. | |
170 | * @iot: The bank timing information. | |
171 | * | |
172 | * Set the IO bank information from the details calculated earlier from | |
173 | * calling s3c2412_iotiming_calc(). | |
174 | */ | |
175 | void s3c2412_iotiming_set(struct s3c_cpufreq_config *cfg, | |
176 | struct s3c_iotimings *iot) | |
177 | { | |
178 | struct s3c2412_iobank_timing *bt; | |
179 | void __iomem *regs; | |
180 | int bank; | |
181 | ||
182 | /* set the io timings from the specifier */ | |
183 | ||
184 | for (bank = 0; bank < MAX_BANKS; bank++) { | |
185 | bt = iot->bank[bank].io_2412; | |
186 | if (!bt) | |
187 | continue; | |
188 | ||
189 | regs = S3C2412_SSMC_BANK(bank); | |
190 | ||
191 | __raw_writel(bt->smbidcyr, regs + SMBIDCYR); | |
192 | __raw_writel(bt->smbwstrd, regs + SMBWSTRDR); | |
193 | __raw_writel(bt->smbwstwr, regs + SMBWSTWRR); | |
194 | __raw_writel(bt->smbwstoen, regs + SMBWSTOENR); | |
195 | __raw_writel(bt->smbwstwen, regs + SMBWSTWENR); | |
196 | __raw_writel(bt->smbwstbrd, regs + SMBWSTBRDR); | |
197 | } | |
198 | } | |
199 | ||
200 | static inline unsigned int s3c2412_decode_timing(unsigned int clock, u32 reg) | |
201 | { | |
202 | return (reg & 0xf) * clock; | |
203 | } | |
204 | ||
205 | static void s3c2412_iotiming_getbank(struct s3c_cpufreq_config *cfg, | |
206 | struct s3c2412_iobank_timing *bt, | |
207 | unsigned int bank) | |
208 | { | |
209 | unsigned long clk = cfg->freq.hclk_tns; /* ssmc clock??? */ | |
210 | void __iomem *regs = S3C2412_SSMC_BANK(bank); | |
211 | ||
212 | bt->idcy = s3c2412_decode_timing(clk, __raw_readl(regs + SMBIDCYR)); | |
213 | bt->wstrd = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTRDR)); | |
214 | bt->wstoen = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTOENR)); | |
215 | bt->wstwen = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTWENR)); | |
216 | bt->wstbrd = s3c2412_decode_timing(clk, __raw_readl(regs + SMBWSTBRDR)); | |
217 | } | |
218 | ||
219 | /** | |
220 | * bank_is_io - return true if bank is (possibly) IO. | |
221 | * @bank: The bank number. | |
222 | * @bankcfg: The value of S3C2412_EBI_BANKCFG. | |
223 | */ | |
224 | static inline bool bank_is_io(unsigned int bank, u32 bankcfg) | |
225 | { | |
226 | if (bank < 2) | |
227 | return true; | |
228 | ||
229 | return !(bankcfg & (1 << bank)); | |
230 | } | |
231 | ||
232 | int s3c2412_iotiming_get(struct s3c_cpufreq_config *cfg, | |
233 | struct s3c_iotimings *timings) | |
234 | { | |
235 | struct s3c2412_iobank_timing *bt; | |
236 | u32 bankcfg = __raw_readl(S3C2412_EBI_BANKCFG); | |
237 | unsigned int bank; | |
238 | ||
239 | /* look through all banks to see what is currently set. */ | |
240 | ||
241 | for (bank = 0; bank < MAX_BANKS; bank++) { | |
242 | if (!bank_is_io(bank, bankcfg)) | |
243 | continue; | |
244 | ||
245 | bt = kzalloc(sizeof(struct s3c2412_iobank_timing), GFP_KERNEL); | |
246 | if (!bt) { | |
247 | printk(KERN_ERR "%s: no memory for bank\n", __func__); | |
248 | return -ENOMEM; | |
249 | } | |
250 | ||
251 | timings->bank[bank].io_2412 = bt; | |
252 | s3c2412_iotiming_getbank(cfg, bt, bank); | |
253 | } | |
254 | ||
255 | s3c2412_print_timing("get", timings); | |
256 | return 0; | |
257 | } | |
258 | ||
259 | /* this is in here as it is so small, it doesn't currently warrant a file | |
260 | * to itself. We expect that any s3c24xx needing this is going to also | |
261 | * need the iotiming support. | |
262 | */ | |
263 | void s3c2412_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg) | |
264 | { | |
265 | struct s3c_cpufreq_board *board = cfg->board; | |
266 | u32 refresh; | |
267 | ||
268 | WARN_ON(board == NULL); | |
269 | ||
270 | /* Reduce both the refresh time (in ns) and the frequency (in MHz) | |
271 | * down to ensure that we do not overflow 32 bit numbers. | |
272 | * | |
273 | * This should work for HCLK up to 133MHz and refresh period up | |
274 | * to 30usec. | |
275 | */ | |
276 | ||
277 | refresh = (cfg->freq.hclk / 100) * (board->refresh / 10); | |
278 | refresh = DIV_ROUND_UP(refresh, (1000 * 1000)); /* apply scale */ | |
279 | refresh &= ((1 << 16) - 1); | |
280 | ||
281 | s3c_freq_dbg("%s: refresh value %u\n", __func__, (unsigned int)refresh); | |
282 | ||
283 | __raw_writel(refresh, S3C2412_REFRESH); | |
284 | } |