3 * Daniel Engström, Omicron Ceti AB <daniel@omicron.se>.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24 /* This file is largely based on code obtned from AMD. AMD's original
25 * copyright is included below
29 * =============================================================================
31 * Copyright 1999 Advanced Micro Devices, Inc.
33 * This software is the property of Advanced Micro Devices, Inc (AMD) which
34 * specifically grants the user the right to modify, use and distribute this
35 * software provided this COPYRIGHT NOTICE is not removed or altered. All
36 * other rights are reserved by AMD.
38 * THE MATERIALS ARE PROVIDED "AS IS" WITHOUT ANY EXPRESS OR IMPLIED WARRANTY
39 * OF ANY KIND INCLUDING WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT OF
40 * THIRD-PARTY INTELLECTUAL PROPERTY, OR FITNESS FOR ANY PARTICULAR PURPOSE.
41 * IN NO EVENT SHALL AMD OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER
42 * (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS
43 * INTERRUPTION, LOSS OF INFORMAITON) ARISING OUT OF THE USE OF OR INABILITY
44 * TO USE THE MATERIALS, EVEN IF AMD HAS BEEN ADVISED OF THE POSSIBILITY OF
45 * SUCH DAMAGES. BECAUSE SOME JURSIDICTIONS PROHIBIT THE EXCLUSION OR
46 * LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, THE ABOVE
47 * LIMITATION MAY NOT APPLY TO YOU.
49 * AMD does not assume any responsibility for any errors that may appear in
50 * the Materials nor any responsibility to support or update the Materials.
51 * AMD retains the right to make changes to its test specifications at any
52 * time, without notice.
54 * So that all may benefit from your experience, please report any problems
55 * or suggestions about this software back to AMD. Please include your name,
56 * company, telephone number, AMD product requiring support and question or
57 * problem encountered.
59 * Advanced Micro Devices, Inc. Worldwide support and contact
60 * Embedded Processor Division information available at:
61 * Systems Engineering epd.support@amd.com
62 * 5204 E. Ben White Blvd. -or-
63 * Austin, TX 78741 http://www.amd.com/html/support/techsup.html
64 * ============================================================================
68 /*******************************************************************************
69 * AUTHOR : Buddy Fey - Original.
70 *******************************************************************************
74 /*******************************************************************************
75 * FUNCTIONAL DESCRIPTION:
76 * This routine is called to autodetect the geometry of the DRAM.
78 * This routine is called to determine the number of column bits for the DRAM
79 * devices in this external bank. This routine assumes that the external bank
80 * has been configured for an 11-bit column and for 4 internal banks. This gives
81 * us the maximum address reach in memory. By writing a test value to the max
82 * address and locating where it aliases to, we can determine the number of valid
85 * This routine is called to determine the number of internal banks each DRAM
86 * device has. The external bank (under test) is configured for maximum reach
87 * with 11-bit columns and 4 internal banks. This routine will write to a max
88 * address (BA1 and BA0 = 1) and then read from an address with BA1=0 to see if
89 * that column is a "don't care". If BA1 does not affect write/read of data,
90 * then this device has only 2 internal banks.
92 * This routine is called to determine the ending address for this external
93 * bank of SDRAM. We write to a max address with a data value and then disable
94 * row address bits looking for "don't care" locations. Each "don't care" bit
95 * represents a dividing of the maximum density (128M) by 2. By dividing the
96 * maximum of 32 4M chunks in an external bank down by all the "don't care" bits
97 * determined during sizing, we set the proper density.
100 * bp must be preserved because it is used for return linkage.
103 * nothing returned - but the memory subsystem is enabled
104 *******************************************************************************
108 .equ DRCCTL, 0x0fffef010 /* DRAM control register */
109 .equ DRCTMCTL, 0x0fffef012 /* DRAM timing control register */
110 .equ DRCCFG, 0x0fffef014 /* DRAM bank configuration register */
111 .equ DRCBENDADR, 0x0fffef018 /* DRAM bank ending address register */
112 .equ ECCCTL, 0x0fffef020 /* DRAM ECC control register */
113 .equ DBCTL, 0x0fffef040 /* DRAM buffer control register */
115 .equ CACHELINESZ, 0x00000010 /* size of our cache line (read buffer) */
116 .equ COL11_ADR, 0x0e001e00 /* 11 col addrs */
117 .equ COL10_ADR, 0x0e000e00 /* 10 col addrs */
118 .equ COL09_ADR, 0x0e000600 /* 9 col addrs */
119 .equ COL08_ADR, 0x0e000200 /* 8 col addrs */
120 .equ ROW14_ADR, 0x0f000000 /* 14 row addrs */
121 .equ ROW13_ADR, 0x07000000 /* 13 row addrs */
122 .equ ROW12_ADR, 0x03000000 /* 12 row addrs */
123 .equ ROW11_ADR, 0x01000000 /* 11 row addrs/also bank switch */
124 .equ ROW10_ADR, 0x00000000 /* 10 row addrs/also bank switch */
125 .equ COL11_DATA, 0x0b0b0b0b /* 11 col addrs */
126 .equ COL10_DATA, 0x0a0a0a0a /* 10 col data */
127 .equ COL09_DATA, 0x09090909 /* 9 col data */
128 .equ COL08_DATA, 0x08080808 /* 8 col data */
129 .equ ROW14_DATA, 0x3f3f3f3f /* 14 row data (MASK) */
130 .equ ROW13_DATA, 0x1f1f1f1f /* 13 row data (MASK) */
131 .equ ROW12_DATA, 0x0f0f0f0f /* 12 row data (MASK) */
132 .equ ROW11_DATA, 0x07070707 /* 11 row data/also bank switch (MASK) */
133 .equ ROW10_DATA, 0xaaaaaaaa /* 10 row data/also bank switch (MASK) */
137 * initialize dram controller registers
143 fs movb %al, (%edi) /* disable write buffer */
146 fs movb %al, (%edi) /* disable ECC */
149 movb $0x1E,%al /* Set SDRAM timing for slowest */
153 * setup loop to do 4 external banks starting with bank 3
155 movl $0xff000000,%eax /* enable last bank and setup */
156 movl $DRCBENDADR, %edi /* ending address register */
159 movl $DRCCFG, %edi /* setup */
160 movw $0xbbbb,%ax /* dram config register for */
164 * issue a NOP to all DRAMs
166 movl $DRCCTL, %edi /* setup DRAM control register with */
167 movb $0x1,%al /* Disable refresh,disable write buffer */
169 movl $CACHELINESZ, %esi /* just a dummy address to write for */
172 * delay for 100 usec? 200?
173 * ******this is a cludge for now *************
177 loop sizdelay /* we need 100 usec here */
178 /***********************************************/
181 * issue all banks precharge
183 movb $0x2,%al /* All banks precharge */
188 * issue 2 auto refreshes to all banks
190 movb $0x4,%al /* Auto refresh cmd */
198 * issue LOAD MODE REGISTER command
200 movb $0x3,%al /* Load mode register cmd */
205 * issue 8 more auto refreshes to all banks
207 movb $0x4,%al /* Auto refresh cmd */
215 * set control register to NORMAL mode
217 movb $0x0,%al /* Normal mode value */
221 * size dram starting with external bank 3 moving to external bank 0
223 movl $0x3,%ecx /* start with external bank 3 */
228 * write col 11 wrap adr
230 movl $COL11_ADR, %esi /* set address to max col (11) wrap addr */
231 movl $COL11_DATA, %eax /* pattern for max supported columns(11) */
232 fs movl %eax, (%esi) /* write max col pattern at max col adr */
233 fs movl (%esi), %ebx /* optional read */
234 cmpl %ebx,%eax /* to verify write */
235 jnz bad_ram /* this ram is bad */
237 * write col 10 wrap adr
240 movl $COL10_ADR, %esi /* set address to 10 col wrap address */
241 movl $COL10_DATA, %eax /* pattern for 10 col wrap */
242 fs movl %eax, (%esi) /* write 10 col pattern @ 10 col wrap adr */
243 fs movl (%esi), %ebx /* optional read */
244 cmpl %ebx,%eax /* to verify write */
245 jnz bad_ram /* this ram is bad */
247 * write col 9 wrap adr
249 movl $COL09_ADR, %esi /* set address to 9 col wrap address */
250 movl $COL09_DATA, %eax /* pattern for 9 col wrap */
251 fs movl %eax, (%esi) /* write 9 col pattern @ 9 col wrap adr */
252 fs movl (%esi), %ebx /* optional read */
253 cmpl %ebx,%eax /* to verify write */
254 jnz bad_ram /* this ram is bad */
256 * write col 8 wrap adr
258 movl $COL08_ADR, %esi /* set address to min(8) col wrap address */
259 movl $COL08_DATA, %eax /* pattern for min (8) col wrap */
260 fs movl %eax, (%esi) /* write min col pattern @ min col adr */
261 fs movl (%esi), %ebx /* optional read */
262 cmpl %ebx,%eax /* to verify write */
263 jnz bad_ram /* this ram is bad */
265 * write row 14 wrap adr
267 movl $ROW14_ADR, %esi /* set address to max row (14) wrap addr */
268 movl $ROW14_DATA, %eax /* pattern for max supported rows(14) */
269 fs movl %eax, (%esi) /* write max row pattern at max row adr */
270 fs movl (%esi), %ebx /* optional read */
271 cmpl %ebx,%eax /* to verify write */
272 jnz bad_ram /* this ram is bad */
274 * write row 13 wrap adr
276 movl $ROW13_ADR, %esi /* set address to 13 row wrap address */
277 movl $ROW13_DATA, %eax /* pattern for 13 row wrap */
278 fs movl %eax, (%esi) /* write 13 row pattern @ 13 row wrap adr */
279 fs movl (%esi), %ebx /* optional read */
280 cmpl %ebx,%eax /* to verify write */
281 jnz bad_ram /* this ram is bad */
283 * write row 12 wrap adr
285 movl $ROW12_ADR, %esi /* set address to 12 row wrap address */
286 movl $ROW12_DATA, %eax /* pattern for 12 row wrap */
287 fs movl %eax, (%esi) /* write 12 row pattern @ 12 row wrap adr */
288 fs movl (%esi), %ebx /* optional read */
289 cmpl %ebx,%eax /* to verify write */
290 jnz bad_ram /* this ram is bad */
292 * write row 11 wrap adr
294 movl $ROW11_ADR, %edi /* set address to 11 row wrap address */
295 movl $ROW11_DATA, %eax /* pattern for 11 row wrap */
296 fs movl %eax, (%edi) /* write 11 row pattern @ 11 row wrap adr */
297 fs movl (%edi), %ebx /* optional read */
298 cmpl %ebx,%eax /* to verify write */
299 jnz bad_ram /* this ram is bad */
301 * write row 10 wrap adr --- this write is really to determine number of banks
303 movl $ROW10_ADR, %edi /* set address to 10 row wrap address */
304 movl $ROW10_DATA, %eax /* pattern for 10 row wrap (AA) */
305 fs movl %eax, (%edi) /* write 10 row pattern @ 10 row wrap adr */
306 fs movl (%edi), %ebx /* optional read */
307 cmpl %ebx,%eax /* to verify write */
308 jnz bad_ram /* this ram is bad */
310 * read data @ row 12 wrap adr to determine * banks,
311 * and read data @ row 14 wrap adr to determine * rows.
312 * if data @ row 12 wrap adr is not AA, 11 or 12 we have bad RAM.
313 * if data @ row 12 wrap == AA, we only have 2 banks, NOT 4
314 * if data @ row 12 wrap == 11 or 12, we have 4 banks,
316 xorw %di,%di /* value for 2 banks in DI */
317 fs movl (%esi), %ebx /* read from 12 row wrap to check banks
318 * (esi is setup from the write to row 12 wrap) */
319 cmpl %ebx,%eax /* check for AA pattern (eax holds the aa pattern) */
320 jz only2 /* if pattern == AA, we only have 2 banks */
324 movw $8,%di /* value for 4 banks in DI (BNK_CNT bit) */
325 cmpl $ROW11_DATA, %ebx /* only other legitimate values are 11 */
327 cmpl $ROW12_DATA, %ebx /* and 12 */
328 jnz bad_ram /* its bad if not 11 or 12! */
335 movl $ROW14_ADR, %esi /* set address back to max row wrap addr */
336 fs movl (%esi), %eax /* read actual number of rows @ row14 adr */
338 cmpl $ROW11_DATA, %eax /* row must be greater than 11 pattern */
341 cmpl $ROW14_DATA, %eax /* and row must be less than 14 pattern */
344 cmpb %ah,%al /* verify all 4 bytes of dword same */
351 * read col 11 wrap adr for real column data value
353 movl $COL11_ADR, %esi /* set address to max col (11) wrap addr */
354 fs movl (%esi), %eax /* read real col number at max col adr */
356 * validate column data
358 cmpl $COL08_DATA, %eax /* col must be greater than 8 pattern */
361 cmpl $COL11_DATA, %eax /* and row must be less than 11 pattern */
364 subl $COL08_DATA, %eax /* normalize column data to zero */
366 cmpb %ah,%al /* verify all 4 bytes of dword equal */
373 * merge bank and col data together
375 addw %di,%dx /* merge of bank and col info in dl */
377 * fix ending addr mask based upon col info
380 subb %dh,%al /* dh contains the overflow from the bank/col merge */
381 movb %bl,%dh /* bl contains the row mask (aa, 07, 0f, 1f or 3f) */
382 xchgw %cx,%ax /* cx = ax = 3 or 2 depending on 2 or 4 bank device */
384 incb %dh /* ending addr is 1 greater than real end */
385 xchgw %cx,%ax /* cx is bank number again */
387 * issue all banks precharge
390 movl $DRCCTL, %esi /* setup DRAM control register with */
391 movb $0x2,%al /* All banks precharge */
393 movl $CACHELINESZ, %esi /* address to init read buffer */
397 * update ENDING ADDRESS REGISTER
399 movl $DRCBENDADR, %edi /* DRAM ending address register */
404 * update CONFIG REGISTER
424 movl $DRCBENDADR, %edi /* DRAM ending address register */
429 * set control register to NORMAL mode
431 movl $DRCCTL, %esi /* setup DRAM control register with */
432 movb $0x0,%al /* Normal mode value */
434 movl $CACHELINESZ, %esi /* address to init read buffer */
439 movl $DRCBENDADR, %edi /* DRAM ending address register */
459 #if defined(CFG_SDRAM_CAS_LATENCY_2T) || defined(CFG_SDRAM_CAS_LATENCY_3T)
460 /* set the CAS latency now since it is hard to do
461 * when we run from the RAM */
462 movl $DRCTMCTL, %edi /* DRAM timing register */
464 #ifdef CFG_SDRAM_CAS_LATENCY_2T
467 #ifdef CFG_SDRAM_CAS_LATENCY_3T
472 movl $DRCCTL, %edi /* DRAM Control register */
473 movb $0x3,%al /* Load mode register cmd */
478 movl $DRCCTL, %edi /* DRAM Control register */
479 movb $0x18,%al /* Enable refresh and NORMAL mode */
491 /* readback DRCBENDADR and return the number
492 * of available ram bytes in %eax */
494 movl $DRCBENDADR, %edi /* DRAM ending address register */
498 andl $0x80000000, %ecx
500 andl $0x7f000000, %eax
504 bank2: movl (%edi), %eax
506 andl $0x00800000, %ecx
508 andl $0x007f0000, %eax
512 bank1: movl (%edi), %eax
514 andl $0x00008000, %ecx
516 andl $0x00007f00, %eax
520 bank0: movl (%edi), %eax
522 andl $0x00000080, %ecx
524 andl $0x0000007f, %eax
528 done: movl %ebx, %eax