]> git.ipfire.org Git - people/ms/u-boot.git/blob - board/sixnet/sixnet.c
rename CFG_ macros to CONFIG_SYS
[people/ms/u-boot.git] / board / sixnet / sixnet.c
1 /*
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 <jffs2/jffs2.h>
28 #include <mpc8xx.h>
29 #include <net.h> /* for eth_init() */
30 #include <rtc.h>
31 #include "sixnet.h"
32 #ifdef CONFIG_SHOW_BOOT_PROGRESS
33 # include <status_led.h>
34 #endif
35
36 #if defined(CONFIG_CMD_NAND)
37 #include <linux/mtd/nand_legacy.h>
38 extern struct nand_chip nand_dev_desc[CONFIG_SYS_MAX_NAND_DEVICE];
39 #endif
40
41 DECLARE_GLOBAL_DATA_PTR;
42
43 #define ORMASK(size) ((-size) & OR_AM_MSK)
44
45 static long ram_size(ulong *, long);
46
47 /* ------------------------------------------------------------------------- */
48
49 #ifdef CONFIG_SHOW_BOOT_PROGRESS
50 void show_boot_progress (int status)
51 {
52 #if defined(CONFIG_STATUS_LED)
53 # if defined(STATUS_LED_BOOT)
54 if (status == 15) {
55 /* ready to transfer to kernel, make sure LED is proper state */
56 status_led_set(STATUS_LED_BOOT, CONFIG_BOOT_LED_STATE);
57 }
58 # endif /* STATUS_LED_BOOT */
59 #endif /* CONFIG_STATUS_LED */
60 }
61 #endif
62
63 /* ------------------------------------------------------------------------- */
64
65 /*
66 * Check Board Identity:
67 * returns 0 if recognized, -1 if unknown
68 */
69
70 int checkboard (void)
71 {
72 puts ("Board: SIXNET SXNI855T\n");
73 return 0;
74 }
75
76 /* ------------------------------------------------------------------------- */
77
78 #if defined(CONFIG_CMD_PCMCIA)
79 #error "SXNI855T has no PCMCIA port"
80 #endif
81
82 /* ------------------------------------------------------------------------- */
83
84 #define _not_used_ 0xffffffff
85
86 /* UPMB table for dual UART. */
87
88 /* this table is for 50MHz operation, it should work at all lower speeds */
89 const uint duart_table[] =
90 {
91 /* single read. (offset 0 in upm RAM) */
92 0xfffffc04, 0x0ffffc04, 0x0ff3fc04, 0x0ff3fc04,
93 0x0ff3fc00, 0x0ff3fc04, 0xfffffc04, 0xfffffc05,
94
95 /* burst read. (offset 8 in upm RAM) */
96 _not_used_, _not_used_, _not_used_, _not_used_,
97 _not_used_, _not_used_, _not_used_, _not_used_,
98 _not_used_, _not_used_, _not_used_, _not_used_,
99 _not_used_, _not_used_, _not_used_, _not_used_,
100
101 /* single write. (offset 18 in upm RAM) */
102 0xfffffc04, 0x0ffffc04, 0x00fffc04, 0x00fffc04,
103 0x00fffc04, 0x00fffc00, 0xfffffc04, 0xfffffc05,
104
105 /* burst write. (offset 20 in upm RAM) */
106 _not_used_, _not_used_, _not_used_, _not_used_,
107 _not_used_, _not_used_, _not_used_, _not_used_,
108 _not_used_, _not_used_, _not_used_, _not_used_,
109 _not_used_, _not_used_, _not_used_, _not_used_,
110
111 /* refresh. (offset 30 in upm RAM) */
112 _not_used_, _not_used_, _not_used_, _not_used_,
113 _not_used_, _not_used_, _not_used_, _not_used_,
114 _not_used_, _not_used_, _not_used_, _not_used_,
115
116 /* exception. (offset 3c in upm RAM) */
117 _not_used_, _not_used_, _not_used_, _not_used_,
118 };
119
120 /* Load FPGA very early in boot sequence, since it must be
121 * loaded before the 16C2550 serial channels can be used as
122 * console channels.
123 *
124 * Note: Much of the configuration is not complete. The
125 * stack is in DPRAM since SDRAM has not been initialized,
126 * so the stack must be kept small. Global variables
127 * are still in FLASH, so they cannot be written.
128 * Only the FLASH, DPRAM, immap and FPGA can be addressed,
129 * the other chip selects may not have been initialized.
130 * The clocks have been initialized, so udelay() can be
131 * used.
132 */
133 #define FPGA_DONE 0x0080 /* PA8, input, high when FPGA load complete */
134 #define FPGA_PROGRAM_L 0x0040 /* PA9, output, low to reset, high to start */
135 #define FPGA_INIT_L 0x0020 /* PA10, input, low indicates not ready */
136 #define fpga (*(volatile unsigned char *)(CONFIG_SYS_FPGA_PROG)) /* FPGA port */
137
138 int board_postclk_init (void)
139 {
140
141 /* the data to load to the XCSxxXL FPGA */
142 static const unsigned char fpgadata[] = {
143 # include "fpgadata.c"
144 };
145
146 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
147 volatile memctl8xx_t *memctl = &immap->im_memctl;
148 #define porta (immap->im_ioport.iop_padat)
149 const unsigned char* pdata;
150
151 /* /INITFPGA and DONEFPGA signals are inputs */
152 immap->im_ioport.iop_padir &= ~(FPGA_INIT_L | FPGA_DONE);
153
154 /* Force output pin to begin at 0, /PROGRAM asserted (0) resets FPGA */
155 porta &= ~FPGA_PROGRAM_L;
156
157 /* Set FPGA as an output */
158 immap->im_ioport.iop_padir |= FPGA_PROGRAM_L;
159
160 /* delay a little to make sure FPGA sees it, really
161 * only need less than a microsecond.
162 */
163 udelay(10);
164
165 /* unassert /PROGRAM */
166 porta |= FPGA_PROGRAM_L;
167
168 /* delay while FPGA does last erase, indicated by
169 * /INITFPGA going high. This should happen within a
170 * few milliseconds.
171 */
172 /* ### FIXME - a timeout check would be good, maybe flash
173 * the status LED to indicate the error?
174 */
175 while ((porta & FPGA_INIT_L) == 0)
176 ; /* waiting */
177
178 /* write program data to FPGA at the programming address
179 * so extra /CS1 strobes at end of configuration don't actually
180 * write to any registers.
181 */
182 fpga = 0xff; /* first write is ignored */
183 fpga = 0xff; /* fill byte */
184 fpga = 0xff; /* fill byte */
185 fpga = 0x4f; /* preamble code */
186 fpga = 0x80; fpga = 0xaf; fpga = 0x9b; /* length (ignored) */
187 fpga = 0x4b; /* field check code */
188
189 pdata = fpgadata;
190 /* while no error write out each of the 28 byte frames */
191 while ((porta & (FPGA_INIT_L | FPGA_DONE)) == FPGA_INIT_L
192 && pdata < fpgadata + sizeof(fpgadata)) {
193
194 fpga = 0x4f; /* preamble code */
195
196 /* 21 bytes of data in a frame */
197 fpga = *(pdata++); fpga = *(pdata++);
198 fpga = *(pdata++); fpga = *(pdata++);
199 fpga = *(pdata++); fpga = *(pdata++);
200 fpga = *(pdata++); fpga = *(pdata++);
201 fpga = *(pdata++); fpga = *(pdata++);
202 fpga = *(pdata++); fpga = *(pdata++);
203 fpga = *(pdata++); fpga = *(pdata++);
204 fpga = *(pdata++); fpga = *(pdata++);
205 fpga = *(pdata++); fpga = *(pdata++);
206 fpga = *(pdata++); fpga = *(pdata++);
207 fpga = *(pdata++);
208
209 fpga = 0x4b; /* field check code */
210 fpga = 0xff; /* extended write cycle */
211 fpga = 0x4b; /* extended write cycle
212 * (actually 0x4b from bitgen.exe)
213 */
214 fpga = 0xff; /* extended write cycle */
215 fpga = 0xff; /* extended write cycle */
216 fpga = 0xff; /* extended write cycle */
217 }
218
219 fpga = 0xff; /* startup byte */
220 fpga = 0xff; /* startup byte */
221 fpga = 0xff; /* startup byte */
222 fpga = 0xff; /* startup byte */
223
224 #if 0 /* ### FIXME */
225 /* If didn't load all the data or FPGA_DONE is low the load failed.
226 * Maybe someday stop here and flash the status LED? The console
227 * is not configured, so can't print an error message. Can't write
228 * global variables to set a flag (except gd?).
229 * For now it must work.
230 */
231 #endif
232
233 /* Now that the FPGA is loaded, set up the Dual UART chip
234 * selects. Must be done here since it may be used as the console.
235 */
236 upmconfig(UPMB, (uint *)duart_table, sizeof(duart_table)/sizeof(uint));
237
238 memctl->memc_mbmr = DUART_MBMR;
239 memctl->memc_or5 = DUART_OR_VALUE;
240 memctl->memc_br5 = DUART_BR5_VALUE;
241 memctl->memc_or6 = DUART_OR_VALUE;
242 memctl->memc_br6 = DUART_BR6_VALUE;
243
244 return (0);
245 }
246
247 /* ------------------------------------------------------------------------- */
248
249 /* base address for SRAM, assume 32-bit port, valid */
250 #define NVRAM_BR_VALUE (CONFIG_SYS_SRAM_BASE | BR_PS_32 | BR_V)
251
252 /* up to 64MB - will be adjusted for actual size */
253 #define NVRAM_OR_PRELIM (ORMASK(CONFIG_SYS_SRAM_SIZE) \
254 | OR_CSNT_SAM | OR_ACS_DIV4 | OR_BI | OR_SCY_5_CLK | OR_EHTR)
255 /*
256 * Miscellaneous platform dependent initializations after running in RAM.
257 */
258
259 int misc_init_r (void)
260 {
261 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
262 volatile memctl8xx_t *memctl = &immap->im_memctl;
263 char* s;
264 char* e;
265 int reg;
266 bd_t *bd = gd->bd;
267
268 memctl->memc_or2 = NVRAM_OR_PRELIM;
269 memctl->memc_br2 = NVRAM_BR_VALUE;
270
271 /* Is there any SRAM? Is it 16 or 32 bits wide? */
272
273 /* First look for 32-bit SRAM */
274 bd->bi_sramsize = ram_size((ulong*)CONFIG_SYS_SRAM_BASE, CONFIG_SYS_SRAM_SIZE);
275
276 if (bd->bi_sramsize == 0) {
277 /* no 32-bit SRAM, but there could be 16-bit SRAM since
278 * it would report size 0 when configured for 32-bit bus.
279 * Try again with a 16-bit bus.
280 */
281 memctl->memc_br2 |= BR_PS_16;
282 bd->bi_sramsize = ram_size((ulong*)CONFIG_SYS_SRAM_BASE, CONFIG_SYS_SRAM_SIZE);
283 }
284
285 if (bd->bi_sramsize == 0) {
286 memctl->memc_br2 = 0; /* disable select since nothing there */
287 }
288 else {
289 /* adjust or2 for actual size of SRAM */
290 memctl->memc_or2 |= ORMASK(bd->bi_sramsize);
291 bd->bi_sramstart = CONFIG_SYS_SRAM_BASE;
292 printf("SRAM: %lu KB\n", bd->bi_sramsize >> 10);
293 }
294
295
296 /* set standard MPC8xx clock so kernel will see the time
297 * even if it doesn't have a DS1306 clock driver.
298 * This helps with experimenting with standard kernels.
299 */
300 {
301 ulong tim;
302 struct rtc_time tmp;
303
304 rtc_get(&tmp); /* get time from DS1306 RTC */
305
306 /* convert to seconds since 1970 */
307 tim = mktime(tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
308 tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
309
310 immap->im_sitk.sitk_rtck = KAPWR_KEY;
311 immap->im_sit.sit_rtc = tim;
312 }
313
314 /* set up ethernet address for SCC ethernet. If eth1addr
315 * is present it gets a unique address, otherwise it
316 * shares the FEC address.
317 */
318 s = getenv("eth1addr");
319 if (s == NULL)
320 s = getenv("ethaddr");
321 for (reg=0; reg<6; ++reg) {
322 bd->bi_enet1addr[reg] = s ? simple_strtoul(s, &e, 16) : 0;
323 if (s)
324 s = (*e) ? e+1 : e;
325 }
326
327 return (0);
328 }
329
330 #if defined(CONFIG_CMD_NAND)
331 void nand_init(void)
332 {
333 unsigned long totlen = nand_probe(CONFIG_SYS_DFLASH_BASE);
334
335 printf ("%4lu MB\n", totlen >> 20);
336 }
337 #endif
338
339 /* ------------------------------------------------------------------------- */
340
341 /*
342 * Check memory range for valid RAM. A simple memory test determines
343 * the actually available RAM size between addresses `base' and
344 * `base + maxsize'.
345 *
346 * The memory size MUST be a power of 2 for this to work.
347 *
348 * The only memory modified is 8 bytes at offset 0. This is important
349 * since for the SRAM this location is reserved for autosizing, so if
350 * it is modified and the board is reset before ram_size() completes
351 * no damage is done. Normally even the memory at 0 is preserved. The
352 * higher SRAM addresses may contain battery backed RAM disk data which
353 * must never be corrupted.
354 */
355
356 static long ram_size(ulong *base, long maxsize)
357 {
358 volatile long *test_addr;
359 volatile ulong *base_addr = base;
360 ulong ofs; /* byte offset from base_addr */
361 ulong save; /* to make test non-destructive */
362 ulong save2; /* to make test non-destructive */
363 long ramsize = -1; /* size not determined yet */
364
365 save = *base_addr; /* save value at 0 so can restore */
366 save2 = *(base_addr+1); /* save value at 4 so can restore */
367
368 /* is any SRAM present? */
369 *base_addr = 0x5555aaaa;
370
371 /* It is important to drive the data bus with different data so
372 * it doesn't remember the value and look like RAM that isn't there.
373 */
374 *(base_addr + 1) = 0xaaaa5555; /* use write to modify data bus */
375
376 if (*base_addr != 0x5555aaaa)
377 ramsize = 0; /* no RAM present, or defective */
378 else {
379 *base_addr = 0xaaaa5555;
380 *(base_addr + 1) = 0x5555aaaa; /* use write to modify data bus */
381 if (*base_addr != 0xaaaa5555)
382 ramsize = 0; /* no RAM present, or defective */
383 }
384
385 /* now size it if any is present */
386 for (ofs = 4; ofs < maxsize && ramsize < 0; ofs <<= 1) {
387 test_addr = (long*)((long)base_addr + ofs); /* location to test */
388
389 *base_addr = ~*test_addr;
390 if (*base_addr == *test_addr)
391 ramsize = ofs; /* wrapped back to 0, so this is the size */
392 }
393
394 *base_addr = save; /* restore value at 0 */
395 *(base_addr+1) = save2; /* restore value at 4 */
396 return (ramsize);
397 }
398
399 /* ------------------------------------------------------------------------- */
400 /* sdram table based on the FADS manual */
401 /* for chip MB811171622A-100 */
402
403 /* this table is for 50MHz operation, it should work at all lower speeds */
404
405 const uint sdram_table[] =
406 {
407 /* single read. (offset 0 in upm RAM) */
408 0x1f07fc04, 0xeeaefc04, 0x11adfc04, 0xefbbbc00,
409 0x1ff77c47,
410
411 /* precharge and Mode Register Set initialization (offset 5).
412 * This is also entered at offset 6 to do Mode Register Set
413 * without the precharge.
414 */
415 0x1ff77c34, 0xefeabc34, 0x1fb57c35,
416
417 /* burst read. (offset 8 in upm RAM) */
418 0x1f07fc04, 0xeeaefc04, 0x10adfc04, 0xf0affc00,
419 0xf0affc00, 0xf1affc00, 0xefbbbc00, 0x1ff77c47,
420 _not_used_, _not_used_, _not_used_, _not_used_,
421 _not_used_, _not_used_, _not_used_, _not_used_,
422
423 /* single write. (offset 18 in upm RAM) */
424 /* FADS had 0x1f27fc04, ...
425 * but most other boards have 0x1f07fc04, which
426 * sets GPL0 from A11MPC to 0 1/4 clock earlier,
427 * like the single read.
428 * This seems better so I am going with the change.
429 */
430 0x1f07fc04, 0xeeaebc00, 0x01b93c04, 0x1ff77c47,
431 _not_used_, _not_used_, _not_used_, _not_used_,
432
433 /* burst write. (offset 20 in upm RAM) */
434 0x1f07fc04, 0xeeaebc00, 0x10ad7c00, 0xf0affc00,
435 0xf0affc00, 0xe1bbbc04, 0x1ff77c47, _not_used_,
436 _not_used_, _not_used_, _not_used_, _not_used_,
437 _not_used_, _not_used_, _not_used_, _not_used_,
438
439 /* refresh. (offset 30 in upm RAM) */
440 0x1ff5fc84, 0xfffffc04, 0xfffffc04, 0xfffffc04,
441 0xfffffc84, 0xfffffc07, _not_used_, _not_used_,
442 _not_used_, _not_used_, _not_used_, _not_used_,
443
444 /* exception. (offset 3c in upm RAM) */
445 0x7ffffc07, _not_used_, _not_used_, _not_used_ };
446
447 /* ------------------------------------------------------------------------- */
448
449 #define SDRAM_MAX_SIZE 0x10000000 /* max 256 MB SDRAM */
450
451 /* precharge and set Mode Register */
452 #define SDRAM_MCR_PRE (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
453 MCR_MB_CS3 | /* chip select */ \
454 MCR_MLCF(1) | MCR_MAD(5)) /* 1 time at 0x05 */
455
456 /* set Mode Register, no precharge */
457 #define SDRAM_MCR_MRS (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
458 MCR_MB_CS3 | /* chip select */ \
459 MCR_MLCF(1) | MCR_MAD(6)) /* 1 time at 0x06 */
460
461 /* runs refresh loop twice so get 8 refresh cycles */
462 #define SDRAM_MCR_REFR (MCR_OP_RUN | MCR_UPM_A | /* select UPM */ \
463 MCR_MB_CS3 | /* chip select */ \
464 MCR_MLCF(2) | MCR_MAD(0x30)) /* twice at 0x30 */
465
466 /* MAMR values work in either mamr or mbmr */
467 #define SDRAM_MAMR_BASE /* refresh at 50MHz */ \
468 ((195 << MAMR_PTA_SHIFT) | MAMR_PTAE \
469 | MAMR_DSA_1_CYCL /* 1 cycle disable */ \
470 | MAMR_RLFA_1X /* Read loop 1 time */ \
471 | MAMR_WLFA_1X /* Write loop 1 time */ \
472 | MAMR_TLFA_4X) /* Timer loop 4 times */
473 /* 8 column SDRAM */
474 #define SDRAM_MAMR_8COL (SDRAM_MAMR_BASE \
475 | MAMR_AMA_TYPE_0 /* Address MUX 0 */ \
476 | MAMR_G0CLA_A11) /* GPL0 A11[MPC] */
477
478 /* 9 column SDRAM */
479 #define SDRAM_MAMR_9COL (SDRAM_MAMR_BASE \
480 | MAMR_AMA_TYPE_1 /* Address MUX 1 */ \
481 | MAMR_G0CLA_A10) /* GPL0 A10[MPC] */
482
483 /* base address 0, 32-bit port, SDRAM UPM, valid */
484 #define SDRAM_BR_VALUE (BR_PS_32 | BR_MS_UPMA | BR_V)
485
486 /* up to 256MB, SAM, G5LS - will be adjusted for actual size */
487 #define SDRAM_OR_PRELIM (ORMASK(SDRAM_MAX_SIZE) | OR_CSNT_SAM | OR_G5LS)
488
489 /* This is the Mode Select Register value for the SDRAM.
490 * Burst length: 4
491 * Burst Type: sequential
492 * CAS Latency: 2
493 * Write Burst Length: burst
494 */
495 #define SDRAM_MODE 0x22 /* CAS latency 2, burst length 4 */
496
497 /* ------------------------------------------------------------------------- */
498
499 phys_size_t initdram(int board_type)
500 {
501 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
502 volatile memctl8xx_t *memctl = &immap->im_memctl;
503 uint size_sdram = 0;
504 uint size_sdram9 = 0;
505 uint base = 0; /* SDRAM must start at 0 */
506 int i;
507
508 upmconfig(UPMA, (uint *)sdram_table, sizeof(sdram_table)/sizeof(uint));
509
510 /* Configure the refresh (mostly). This needs to be
511 * based upon processor clock speed and optimized to provide
512 * the highest level of performance.
513 *
514 * Preliminary prescaler for refresh.
515 * This value is selected for four cycles in 31.2 us,
516 * which gives 8192 cycles in 64 milliseconds.
517 * This may be too fast, but works for any memory.
518 * It is adjusted to 4096 cycles in 64 milliseconds if
519 * possible once we know what memory we have.
520 *
521 * We have to be careful changing UPM registers after we
522 * ask it to run these commands.
523 *
524 * PTA - periodic timer period for our design is
525 * 50 MHz x 31.2us
526 * --------------- = 195
527 * 1 x 8 x 1
528 *
529 * 50MHz clock
530 * 31.2us refresh interval
531 * SCCR[DFBRG] 0
532 * PTP divide by 8
533 * 1 chip select
534 */
535 memctl->memc_mptpr = MPTPR_PTP_DIV8; /* 0x0800 */
536 memctl->memc_mamr = SDRAM_MAMR_8COL & (~MAMR_PTAE); /* no refresh yet */
537
538 /* The SDRAM Mode Register value is shifted left 2 bits since
539 * A30 and A31 don't connect to the SDRAM for 32-bit wide memory.
540 */
541 memctl->memc_mar = SDRAM_MODE << 2; /* MRS code */
542 udelay(200); /* SDRAM needs 200uS before set it up */
543
544 /* Now run the precharge/nop/mrs commands. */
545 memctl->memc_mcr = SDRAM_MCR_PRE;
546 udelay(2);
547
548 /* Run 8 refresh cycles (2 sets of 4) */
549 memctl->memc_mcr = SDRAM_MCR_REFR; /* run refresh twice */
550 udelay(2);
551
552 /* some brands want Mode Register set after the refresh
553 * cycles. This shouldn't hurt anything for the brands
554 * that were happy with the first time we set it.
555 */
556 memctl->memc_mcr = SDRAM_MCR_MRS;
557 udelay(2);
558
559 memctl->memc_mamr = SDRAM_MAMR_8COL; /* enable refresh */
560 memctl->memc_or3 = SDRAM_OR_PRELIM;
561 memctl->memc_br3 = SDRAM_BR_VALUE + base;
562
563 /* Some brands need at least 10 DRAM accesses to stabilize.
564 * It wont hurt the brands that don't.
565 */
566 for (i=0; i<10; ++i) {
567 volatile ulong *addr = (volatile ulong *)base;
568 ulong val;
569
570 val = *(addr + i);
571 *(addr + i) = val;
572 }
573
574 /* Check SDRAM memory Size in 8 column mode.
575 * For a 9 column memory we will get half the actual size.
576 */
577 size_sdram = ram_size((ulong *)0, SDRAM_MAX_SIZE);
578
579 /* Check SDRAM memory Size in 9 column mode.
580 * For an 8 column memory we will see at most 4 megabytes.
581 */
582 memctl->memc_mamr = SDRAM_MAMR_9COL;
583 size_sdram9 = ram_size((ulong *)0, SDRAM_MAX_SIZE);
584
585 if (size_sdram < size_sdram9) /* leave configuration at 9 columns */
586 size_sdram = size_sdram9;
587 else /* go back to 8 columns */
588 memctl->memc_mamr = SDRAM_MAMR_8COL;
589
590 /* adjust or3 for actual size of SDRAM
591 */
592 memctl->memc_or3 |= ORMASK(size_sdram);
593
594 /* Adjust refresh rate depending on SDRAM type.
595 * For types > 128 MBit (32 Mbyte for 2 x16 devices) leave
596 * it at the current (fast) rate.
597 * For 16, 64 and 128 MBit half the rate will do.
598 */
599 if (size_sdram <= 32 * 1024 * 1024)
600 memctl->memc_mptpr = MPTPR_PTP_DIV16; /* 0x0400 */
601
602 return (size_sdram);
603 }