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wdenk5b1d7132002-11-03 00:07:02 +00001/*
2 * (C) Copyright 2001, 2002
3 * Dave Ellis, SIXNET, dge@sixnetio.com.
4 * Based on code by:
5 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6 * and other contributors to U-Boot. See file CREDITS for list
7 * of people who contributed to this project.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22 * MA 02111-1307 USA
23 */
24
25#include <common.h>
26#include <config.h>
27#include <mpc8xx.h>
28#include <net.h> /* for eth_init() */
29#include <rtc.h>
30#include "sixnet.h"
wdenk5840af22003-03-28 14:40:36 +000031#ifdef CONFIG_SHOW_BOOT_PROGRESS
32# include <status_led.h>
33#endif
wdenk5b1d7132002-11-03 00:07:02 +000034
35#define ORMASK(size) ((-size) & OR_AM_MSK)
36
37static long ram_size(ulong *, long);
38
39/* ------------------------------------------------------------------------- */
40
wdenk5840af22003-03-28 14:40:36 +000041#ifdef CONFIG_SHOW_BOOT_PROGRESS
42void show_boot_progress (int status)
43{
44#if defined(CONFIG_STATUS_LED)
45# if defined(STATUS_LED_BOOT)
46 if (status == 15) {
47 /* ready to transfer to kernel, make sure LED is proper state */
48 status_led_set(STATUS_LED_BOOT, CONFIG_BOOT_LED_STATE);
49 }
50# endif /* STATUS_LED_BOOT */
51#endif /* CONFIG_STATUS_LED */
52}
53#endif
54
55/* ------------------------------------------------------------------------- */
56
wdenk5b1d7132002-11-03 00:07:02 +000057/*
58 * Check Board Identity:
59 * returns 0 if recognized, -1 if unknown
60 */
61
62int checkboard (void)
63{
64 puts ("Board: SIXNET SXNI855T\n");
65 return 0;
66}
67
68/* ------------------------------------------------------------------------- */
69
70#if (CONFIG_COMMANDS & CFG_CMD_PCMCIA)
71#error "SXNI855T has no PCMCIA port"
72#endif /* CFG_CMD_PCMCIA */
73
74/* ------------------------------------------------------------------------- */
75
76#define _not_used_ 0xffffffff
77
78/* UPMB table for dual UART. */
79
80/* this table is for 50MHz operation, it should work at all lower speeds */
81const uint duart_table[] =
82{
83 /* single read. (offset 0 in upm RAM) */
84 0xfffffc04, 0x0ffffc04, 0x0ff3fc04, 0x0ff3fc04,
85 0x0ff3fc00, 0x0ff3fc04, 0xfffffc04, 0xfffffc05,
86
87 /* burst read. (offset 8 in upm RAM) */
88 _not_used_, _not_used_, _not_used_, _not_used_,
89 _not_used_, _not_used_, _not_used_, _not_used_,
90 _not_used_, _not_used_, _not_used_, _not_used_,
91 _not_used_, _not_used_, _not_used_, _not_used_,
92
93 /* single write. (offset 18 in upm RAM) */
94 0xfffffc04, 0x0ffffc04, 0x00fffc04, 0x00fffc04,
95 0x00fffc04, 0x00fffc00, 0xfffffc04, 0xfffffc05,
96
97 /* burst write. (offset 20 in upm RAM) */
98 _not_used_, _not_used_, _not_used_, _not_used_,
99 _not_used_, _not_used_, _not_used_, _not_used_,
100 _not_used_, _not_used_, _not_used_, _not_used_,
101 _not_used_, _not_used_, _not_used_, _not_used_,
102
103 /* refresh. (offset 30 in upm RAM) */
104 _not_used_, _not_used_, _not_used_, _not_used_,
105 _not_used_, _not_used_, _not_used_, _not_used_,
106 _not_used_, _not_used_, _not_used_, _not_used_,
107
108 /* exception. (offset 3c in upm RAM) */
109 _not_used_, _not_used_, _not_used_, _not_used_,
110};
111
112/* Load FPGA very early in boot sequence, since it must be
113 * loaded before the 16C2550 serial channels can be used as
114 * console channels.
115 *
116 * Note: Much of the configuration is not complete. The
117 * stack is in DPRAM since SDRAM has not been initialized,
118 * so the stack must be kept small. Global variables
119 * are still in FLASH, so they cannot be written.
120 * Only the FLASH, DPRAM, immap and FPGA can be addressed,
121 * the other chip selects may not have been initialized.
122 * The clocks have been initialized, so udelay() can be
123 * used.
124 */
125#define FPGA_DONE 0x0080 /* PA8, input, high when FPGA load complete */
126#define FPGA_PROGRAM_L 0x0040 /* PA9, output, low to reset, high to start */
127#define FPGA_INIT_L 0x0020 /* PA10, input, low indicates not ready */
128#define fpga (*(volatile unsigned char *)(CFG_FPGA_PROG)) /* FPGA port */
129
130int board_postclk_init (void)
131{
132
133 /* the data to load to the XCSxxXL FPGA */
134 static const unsigned char fpgadata[] = {
135# include "fpgadata.c"
136 };
137
138 volatile immap_t *immap = (immap_t *)CFG_IMMR;
139 volatile memctl8xx_t *memctl = &immap->im_memctl;
140#define porta (immap->im_ioport.iop_padat)
141 const unsigned char* pdata;
142
143 /* /INITFPGA and DONEFPGA signals are inputs */
144 immap->im_ioport.iop_padir &= ~(FPGA_INIT_L | FPGA_DONE);
145
146 /* Force output pin to begin at 0, /PROGRAM asserted (0) resets FPGA */
147 porta &= ~FPGA_PROGRAM_L;
148
149 /* Set FPGA as an output */
150 immap->im_ioport.iop_padir |= FPGA_PROGRAM_L;
151
152 /* delay a little to make sure FPGA sees it, really
153 * only need less than a microsecond.
154 */
155 udelay(10);
156
157 /* unassert /PROGRAM */
158 porta |= FPGA_PROGRAM_L;
159
160 /* delay while FPGA does last erase, indicated by
161 * /INITFPGA going high. This should happen within a
162 * few milliseconds.
163 */
164 /* ### FIXME - a timeout check would be good, maybe flash
165 * the status LED to indicate the error?
166 */
167 while ((porta & FPGA_INIT_L) == 0)
168 ; /* waiting */
169
170 /* write program data to FPGA at the programming address
171 * so extra /CS1 strobes at end of configuration don't actually
172 * write to any registers.
173 */
174 fpga = 0xff; /* first write is ignored */
175 fpga = 0xff; /* fill byte */
176 fpga = 0xff; /* fill byte */
177 fpga = 0x4f; /* preamble code */
178 fpga = 0x80; fpga = 0xaf; fpga = 0x9b; /* length (ignored) */
179 fpga = 0x4b; /* field check code */
180
181 pdata = fpgadata;
182 /* while no error write out each of the 28 byte frames */
183 while ((porta & (FPGA_INIT_L | FPGA_DONE)) == FPGA_INIT_L
184 && pdata < fpgadata + sizeof(fpgadata)) {
185
186 fpga = 0x4f; /* preamble code */
187
188 /* 21 bytes of data in a frame */
189 fpga = *(pdata++); fpga = *(pdata++);
190 fpga = *(pdata++); fpga = *(pdata++);
191 fpga = *(pdata++); fpga = *(pdata++);
192 fpga = *(pdata++); fpga = *(pdata++);
193 fpga = *(pdata++); fpga = *(pdata++);
194 fpga = *(pdata++); fpga = *(pdata++);
195 fpga = *(pdata++); fpga = *(pdata++);
196 fpga = *(pdata++); fpga = *(pdata++);
197 fpga = *(pdata++); fpga = *(pdata++);
198 fpga = *(pdata++); fpga = *(pdata++);
199 fpga = *(pdata++);
200
201 fpga = 0x4b; /* field check code */
202 fpga = 0xff; /* extended write cycle */
203 fpga = 0x4b; /* extended write cycle
204 * (actually 0x4b from bitgen.exe)
205 */
206 fpga = 0xff; /* extended write cycle */
207 fpga = 0xff; /* extended write cycle */
208 fpga = 0xff; /* extended write cycle */
209 }
210
211 fpga = 0xff; /* startup byte */
212 fpga = 0xff; /* startup byte */
213 fpga = 0xff; /* startup byte */
214 fpga = 0xff; /* startup byte */
215
216#if 0 /* ### FIXME */
217 /* If didn't load all the data or FPGA_DONE is low the load failed.
218 * Maybe someday stop here and flash the status LED? The console
219 * is not configured, so can't print an error message. Can't write
220 * global variables to set a flag (except gd?).
221 * For now it must work.
222 */
223#endif
224
225 /* Now that the FPGA is loaded, set up the Dual UART chip
226 * selects. Must be done here since it may be used as the console.
227 */
228 upmconfig(UPMB, (uint *)duart_table, sizeof(duart_table)/sizeof(uint));
229
230 memctl->memc_mbmr = DUART_MBMR;
231 memctl->memc_or5 = DUART_OR_VALUE;
232 memctl->memc_br5 = DUART_BR5_VALUE;
233 memctl->memc_or6 = DUART_OR_VALUE;
234 memctl->memc_br6 = DUART_BR6_VALUE;
235
236 return (0);
237}
238
239/* ------------------------------------------------------------------------- */
240
241/* base address for SRAM, assume 32-bit port, valid */
242#define NVRAM_BR_VALUE (CFG_SRAM_BASE | BR_PS_32 | BR_V)
243
244/* up to 64MB - will be adjusted for actual size */
245#define NVRAM_OR_PRELIM (ORMASK(CFG_SRAM_SIZE) \
246 | OR_CSNT_SAM | OR_ACS_DIV4 | OR_BI | OR_SCY_5_CLK | OR_EHTR)
247/*
248 * Miscellaneous platform dependent initializations after running in RAM.
249 */
250
251int misc_init_r (void)
252{
253 DECLARE_GLOBAL_DATA_PTR;
254
255 volatile immap_t *immap = (immap_t *)CFG_IMMR;
256 volatile memctl8xx_t *memctl = &immap->im_memctl;
wdenk5840af22003-03-28 14:40:36 +0000257 char* s;
258 char* e;
259 int reg;
wdenk5b1d7132002-11-03 00:07:02 +0000260 bd_t *bd = gd->bd;
261
262 memctl->memc_or2 = NVRAM_OR_PRELIM;
263 memctl->memc_br2 = NVRAM_BR_VALUE;
264
265 /* Is there any SRAM? Is it 16 or 32 bits wide? */
266
267 /* First look for 32-bit SRAM */
268 bd->bi_sramsize = ram_size((ulong*)CFG_SRAM_BASE, CFG_SRAM_SIZE);
269
270 if (bd->bi_sramsize == 0) {
271 /* no 32-bit SRAM, but there could be 16-bit SRAM since
272 * it would report size 0 when configured for 32-bit bus.
273 * Try again with a 16-bit bus.
274 */
275 memctl->memc_br2 |= BR_PS_16;
276 bd->bi_sramsize = ram_size((ulong*)CFG_SRAM_BASE, CFG_SRAM_SIZE);
277 }
278
279 if (bd->bi_sramsize == 0) {
280 memctl->memc_br2 = 0; /* disable select since nothing there */
281 }
282 else {
283 /* adjust or2 for actual size of SRAM */
284 memctl->memc_or2 |= ORMASK(bd->bi_sramsize);
285 bd->bi_sramstart = CFG_SRAM_BASE;
286 printf("SRAM: %lu KB\n", bd->bi_sramsize >> 10);
287 }
288
289
290 /* set standard MPC8xx clock so kernel will see the time
291 * even if it doesn't have a DS1306 clock driver.
292 * This helps with experimenting with standard kernels.
293 */
294 {
295 ulong tim;
296 struct rtc_time tmp;
297
298 rtc_get(&tmp); /* get time from DS1306 RTC */
299
300 /* convert to seconds since 1970 */
301 tim = mktime(tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
302 tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
303
304 immap->im_sitk.sitk_rtck = KAPWR_KEY;
305 immap->im_sit.sit_rtc = tim;
306 }
307
wdenk5840af22003-03-28 14:40:36 +0000308 /* set up ethernet address for SCC ethernet. If eth1addr
309 * is present it gets a unique address, otherwise it
310 * shares the FEC address.
wdenk5b1d7132002-11-03 00:07:02 +0000311 */
wdenk5840af22003-03-28 14:40:36 +0000312 s = getenv("eth1addr");
313 if (s == NULL)
314 s = getenv("ethaddr");
315 for (reg=0; reg<6; ++reg) {
316 bd->bi_enet1addr[reg] = s ? simple_strtoul(s, &e, 16) : 0;
317 if (s)
318 s = (*e) ? e+1 : e;
319 }
wdenk5b1d7132002-11-03 00:07:02 +0000320
wdenk5b1d7132002-11-03 00:07:02 +0000321 return (0);
322}
323
324/* ------------------------------------------------------------------------- */
325
326/*
327 * Check memory range for valid RAM. A simple memory test determines
328 * the actually available RAM size between addresses `base' and
329 * `base + maxsize'.
330 *
331 * The memory size MUST be a power of 2 for this to work.
332 *
wdenk5840af22003-03-28 14:40:36 +0000333 * The only memory modified is 8 bytes at offset 0. This is important
wdenk5b1d7132002-11-03 00:07:02 +0000334 * since for the SRAM this location is reserved for autosizing, so if
335 * it is modified and the board is reset before ram_size() completes
336 * no damage is done. Normally even the memory at 0 is preserved. The
337 * higher SRAM addresses may contain battery backed RAM disk data which
338 * must never be corrupted.
339 */
340
341static long ram_size(ulong *base, long maxsize)
342{
343 volatile long *test_addr;
344 volatile long *base_addr = base;
wdenk5b1d7132002-11-03 00:07:02 +0000345 ulong ofs; /* byte offset from base_addr */
346 ulong save; /* to make test non-destructive */
wdenk5840af22003-03-28 14:40:36 +0000347 ulong save2; /* to make test non-destructive */
wdenk5b1d7132002-11-03 00:07:02 +0000348 long ramsize = -1; /* size not determined yet */
349
350 save = *base_addr; /* save value at 0 so can restore */
wdenk5840af22003-03-28 14:40:36 +0000351 save2 = *(base_addr+1); /* save value at 4 so can restore */
wdenk5b1d7132002-11-03 00:07:02 +0000352
353 /* is any SRAM present? */
354 *base_addr = 0x5555aaaa;
355
wdenk5840af22003-03-28 14:40:36 +0000356 /* It is important to drive the data bus with different data so
357 * it doesn't remember the value and look like RAM that isn't there.
wdenk5b1d7132002-11-03 00:07:02 +0000358 */
wdenk5840af22003-03-28 14:40:36 +0000359 *(base_addr + 1) = 0xaaaa5555; /* use write to modify data bus */
wdenk5b1d7132002-11-03 00:07:02 +0000360
361 if (*base_addr != 0x5555aaaa)
362 ramsize = 0; /* no RAM present, or defective */
363 else {
364 *base_addr = 0xaaaa5555;
wdenk5840af22003-03-28 14:40:36 +0000365 *(base_addr + 1) = 0x5555aaaa; /* use write to modify data bus */
wdenk5b1d7132002-11-03 00:07:02 +0000366 if (*base_addr != 0xaaaa5555)
367 ramsize = 0; /* no RAM present, or defective */
368 }
369
370 /* now size it if any is present */
371 for (ofs = 4; ofs < maxsize && ramsize < 0; ofs <<= 1) {
372 test_addr = (long*)((long)base_addr + ofs); /* location to test */
373
374 *base_addr = ~*test_addr;
375 if (*base_addr == *test_addr)
376 ramsize = ofs; /* wrapped back to 0, so this is the size */
377 }
378
379 *base_addr = save; /* restore value at 0 */
wdenk5840af22003-03-28 14:40:36 +0000380 *(base_addr+1) = save2; /* restore value at 4 */
wdenk5b1d7132002-11-03 00:07:02 +0000381 return (ramsize);
382}
383
384/* ------------------------------------------------------------------------- */
385/* sdram table based on the FADS manual */
386/* for chip MB811171622A-100 */
387
388/* this table is for 50MHz operation, it should work at all lower speeds */
389
390const uint sdram_table[] =
391{
392 /* single read. (offset 0 in upm RAM) */
393 0x1f07fc04, 0xeeaefc04, 0x11adfc04, 0xefbbbc00,
394 0x1ff77c47,
395
396 /* precharge and Mode Register Set initialization (offset 5).
397 * This is also entered at offset 6 to do Mode Register Set
398 * without the precharge.
399 */
400 0x1ff77c34, 0xefeabc34, 0x1fb57c35,
401
402 /* burst read. (offset 8 in upm RAM) */
403 0x1f07fc04, 0xeeaefc04, 0x10adfc04, 0xf0affc00,
404 0xf0affc00, 0xf1affc00, 0xefbbbc00, 0x1ff77c47,
405 _not_used_, _not_used_, _not_used_, _not_used_,
406 _not_used_, _not_used_, _not_used_, _not_used_,
407
408 /* single write. (offset 18 in upm RAM) */
409 /* FADS had 0x1f27fc04, ...
410 * but most other boards have 0x1f07fc04, which
411 * sets GPL0 from A11MPC to 0 1/4 clock earlier,
412 * like the single read.
413 * This seems better so I am going with the change.
414 */
415 0x1f07fc04, 0xeeaebc00, 0x01b93c04, 0x1ff77c47,
416 _not_used_, _not_used_, _not_used_, _not_used_,
417
418 /* burst write. (offset 20 in upm RAM) */
419 0x1f07fc04, 0xeeaebc00, 0x10ad7c00, 0xf0affc00,
420 0xf0affc00, 0xe1bbbc04, 0x1ff77c47, _not_used_,
421 _not_used_, _not_used_, _not_used_, _not_used_,
422 _not_used_, _not_used_, _not_used_, _not_used_,
423
424 /* refresh. (offset 30 in upm RAM) */
425 0x1ff5fc84, 0xfffffc04, 0xfffffc04, 0xfffffc04,
426 0xfffffc84, 0xfffffc07, _not_used_, _not_used_,
427 _not_used_, _not_used_, _not_used_, _not_used_,
428
429 /* exception. (offset 3c in upm RAM) */
430 0x7ffffc07, _not_used_, _not_used_, _not_used_ };
431
432/* ------------------------------------------------------------------------- */
433
434#define SDRAM_MAX_SIZE 0x10000000 /* max 256 MB SDRAM */
435
436/* precharge and set Mode Register */
437#define SDRAM_MCR_PRE (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
438 MCR_MB_CS3 | /* chip select */ \
439 MCR_MLCF(1) | MCR_MAD(5)) /* 1 time at 0x05 */
440
441/* set Mode Register, no precharge */
442#define SDRAM_MCR_MRS (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
443 MCR_MB_CS3 | /* chip select */ \
444 MCR_MLCF(1) | MCR_MAD(6)) /* 1 time at 0x06 */
445
446/* runs refresh loop twice so get 8 refresh cycles */
447#define SDRAM_MCR_REFR (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
448 MCR_MB_CS3 | /* chip select */ \
449 MCR_MLCF(2) | MCR_MAD(0x30)) /* twice at 0x30 */
450
451/* MAMR values work in either mamr or mbmr */
wdenk5840af22003-03-28 14:40:36 +0000452#define SDRAM_MAMR_BASE /* refresh at 50MHz */ \
wdenk5b1d7132002-11-03 00:07:02 +0000453 ((195 << MAMR_PTA_SHIFT) | MAMR_PTAE \
wdenk5b1d7132002-11-03 00:07:02 +0000454 | MAMR_DSA_1_CYCL /* 1 cycle disable */ \
wdenk5b1d7132002-11-03 00:07:02 +0000455 | MAMR_RLFA_1X /* Read loop 1 time */ \
456 | MAMR_WLFA_1X /* Write loop 1 time */ \
457 | MAMR_TLFA_4X) /* Timer loop 4 times */
wdenk5840af22003-03-28 14:40:36 +0000458/* 8 column SDRAM */
459#define SDRAM_MAMR_8COL (SDRAM_MAMR_BASE \
460 | MAMR_AMA_TYPE_0 /* Address MUX 0 */ \
461 | MAMR_G0CLA_A11) /* GPL0 A11[MPC] */
wdenk5b1d7132002-11-03 00:07:02 +0000462
463/* 9 column SDRAM */
wdenk5840af22003-03-28 14:40:36 +0000464#define SDRAM_MAMR_9COL (SDRAM_MAMR_BASE \
465 | MAMR_AMA_TYPE_1 /* Address MUX 1 */ \
466 | MAMR_G0CLA_A10) /* GPL0 A10[MPC] */
wdenk5b1d7132002-11-03 00:07:02 +0000467
468/* base address 0, 32-bit port, SDRAM UPM, valid */
469#define SDRAM_BR_VALUE (BR_PS_32 | BR_MS_UPMA | BR_V)
470
471/* up to 256MB, SAM, G5LS - will be adjusted for actual size */
472#define SDRAM_OR_PRELIM (ORMASK(SDRAM_MAX_SIZE) | OR_CSNT_SAM | OR_G5LS)
473
474/* This is the Mode Select Register value for the SDRAM.
475 * Burst length: 4
476 * Burst Type: sequential
477 * CAS Latency: 2
478 * Write Burst Length: burst
479 */
480#define SDRAM_MODE 0x22 /* CAS latency 2, burst length 4 */
481
482/* ------------------------------------------------------------------------- */
483
484long int initdram(int board_type)
485{
486 volatile immap_t *immap = (immap_t *)CFG_IMMR;
487 volatile memctl8xx_t *memctl = &immap->im_memctl;
488 uint size_sdram = 0;
489 uint size_sdram9 = 0;
490 uint base = 0; /* SDRAM must start at 0 */
491 int i;
492
493 upmconfig(UPMA, (uint *)sdram_table, sizeof(sdram_table)/sizeof(uint));
494
495 /* Configure the refresh (mostly). This needs to be
496 * based upon processor clock speed and optimized to provide
497 * the highest level of performance.
498 *
499 * Preliminary prescaler for refresh.
500 * This value is selected for four cycles in 31.2 us,
501 * which gives 8192 cycles in 64 milliseconds.
502 * This may be too fast, but works for any memory.
503 * It is adjusted to 4096 cycles in 64 milliseconds if
504 * possible once we know what memory we have.
505 *
506 * We have to be careful changing UPM registers after we
507 * ask it to run these commands.
508 *
509 * PTA - periodic timer period for our design is
510 * 50 MHz x 31.2us
511 * --------------- = 195
512 * 1 x 8 x 1
513 *
514 * 50MHz clock
515 * 31.2us refresh interval
516 * SCCR[DFBRG] 0
517 * PTP divide by 8
518 * 1 chip select
519 */
520 memctl->memc_mptpr = MPTPR_PTP_DIV8; /* 0x0800 */
521 memctl->memc_mamr = SDRAM_MAMR_8COL & (~MAMR_PTAE); /* no refresh yet */
522
523 /* The SDRAM Mode Register value is shifted left 2 bits since
524 * A30 and A31 don't connect to the SDRAM for 32-bit wide memory.
525 */
526 memctl->memc_mar = SDRAM_MODE << 2; /* MRS code */
527 udelay(200); /* SDRAM needs 200uS before set it up */
528
529 /* Now run the precharge/nop/mrs commands. */
530 memctl->memc_mcr = SDRAM_MCR_PRE;
531 udelay(2);
532
533 /* Run 8 refresh cycles (2 sets of 4) */
534 memctl->memc_mcr = SDRAM_MCR_REFR; /* run refresh twice */
535 udelay(2);
536
537 /* some brands want Mode Register set after the refresh
538 * cycles. This shouldn't hurt anything for the brands
539 * that were happy with the first time we set it.
540 */
541 memctl->memc_mcr = SDRAM_MCR_MRS;
542 udelay(2);
543
544 memctl->memc_mamr = SDRAM_MAMR_8COL; /* enable refresh */
545 memctl->memc_or3 = SDRAM_OR_PRELIM;
546 memctl->memc_br3 = SDRAM_BR_VALUE + base;
547
548 /* Some brands need at least 10 DRAM accesses to stabilize.
549 * It wont hurt the brands that don't.
550 */
551 for (i=0; i<10; ++i) {
552 volatile ulong *addr = (volatile ulong *)base;
553 ulong val;
554
555 val = *(addr + i);
556 *(addr + i) = val;
557 }
558
559 /* Check SDRAM memory Size in 8 column mode.
560 * For a 9 column memory we will get half the actual size.
561 */
562 size_sdram = ram_size((ulong *)0, SDRAM_MAX_SIZE);
563
564 /* Check SDRAM memory Size in 9 column mode.
565 * For an 8 column memory we will see at most 4 megabytes.
566 */
567 memctl->memc_mamr = SDRAM_MAMR_9COL;
568 size_sdram9 = ram_size((ulong *)0, SDRAM_MAX_SIZE);
569
570 if (size_sdram < size_sdram9) /* leave configuration at 9 columns */
571 size_sdram = size_sdram9;
572 else /* go back to 8 columns */
573 memctl->memc_mamr = SDRAM_MAMR_8COL;
574
575 /* adjust or3 for actual size of SDRAM
576 */
577 memctl->memc_or3 |= ORMASK(size_sdram);
578
579 /* Adjust refresh rate depending on SDRAM type.
580 * For types > 128 MBit (32 Mbyte for 2 x16 devices) leave
581 * it at the current (fast) rate.
582 * For 16, 64 and 128 MBit half the rate will do.
583 */
584 if (size_sdram <= 32 * 1024 * 1024)
585 memctl->memc_mptpr = MPTPR_PTP_DIV16; /* 0x0400 */
586
587 return (size_sdram);
588}
589