2 * arch/powerpc/cpu/ppc4xx/40x_spd_sdram.c
3 * This SPD SDRAM detection code supports IBM/AMCC PPC44x cpu with a
4 * SDRAM controller. Those are all current 405 PPC's.
7 * Bill Hunter, Wave 7 Optics, williamhunter@attbi.com
11 * Kenneth Johansson ,Ericsson AB.
12 * kenneth.johansson@etx.ericsson.se
14 * hacked up by bill hunter. fixed so we could run before
15 * serial_init and console_init. previous version avoided this by
16 * running out of cache memory during serial/console init, then running
20 * Jun Gu, Artesyn Technology, jung@artesyncp.com
21 * Support for AMCC 440 based on OpenBIOS draminit.c from IBM.
24 * Stefan Roese, DENX Software Engineering, sr@denx.de.
26 * SPDX-License-Identifier: GPL-2.0+
30 #include <asm/processor.h>
32 #include <asm/ppc4xx.h>
34 #if defined(CONFIG_SPD_EEPROM) && !defined(CONFIG_440)
39 #define ONE_BILLION 1000000000
41 #define SDRAM0_CFG_DCE 0x80000000
42 #define SDRAM0_CFG_SRE 0x40000000
43 #define SDRAM0_CFG_PME 0x20000000
44 #define SDRAM0_CFG_MEMCHK 0x10000000
45 #define SDRAM0_CFG_REGEN 0x08000000
46 #define SDRAM0_CFG_ECCDD 0x00400000
47 #define SDRAM0_CFG_EMDULR 0x00200000
48 #define SDRAM0_CFG_DRW_SHIFT (31-6)
49 #define SDRAM0_CFG_BRPF_SHIFT (31-8)
51 #define SDRAM0_TR_CASL_SHIFT (31-8)
52 #define SDRAM0_TR_PTA_SHIFT (31-13)
53 #define SDRAM0_TR_CTP_SHIFT (31-15)
54 #define SDRAM0_TR_LDF_SHIFT (31-17)
55 #define SDRAM0_TR_RFTA_SHIFT (31-29)
56 #define SDRAM0_TR_RCD_SHIFT (31-31)
58 #define SDRAM0_RTR_SHIFT (31-15)
59 #define SDRAM0_ECCCFG_SHIFT (31-11)
61 /* SDRAM0_CFG enable macro */
62 #define SDRAM0_CFG_BRPF(x) ( ( x & 0x3)<< SDRAM0_CFG_BRPF_SHIFT )
64 #define SDRAM0_BXCR_SZ_MASK 0x000e0000
65 #define SDRAM0_BXCR_AM_MASK 0x0000e000
67 #define SDRAM0_BXCR_SZ_SHIFT (31-14)
68 #define SDRAM0_BXCR_AM_SHIFT (31-18)
70 #define SDRAM0_BXCR_SZ(x) ( (( x << SDRAM0_BXCR_SZ_SHIFT) & SDRAM0_BXCR_SZ_MASK) )
71 #define SDRAM0_BXCR_AM(x) ( (( x << SDRAM0_BXCR_AM_SHIFT) & SDRAM0_BXCR_AM_MASK) )
73 #ifdef CONFIG_SPDDRAM_SILENT
74 # define SPD_ERR(x) do { return 0; } while (0)
76 # define SPD_ERR(x) do { printf(x); return(0); } while (0)
79 #define sdram_HZ_to_ns(hertz) (1000000000/(hertz))
81 /* function prototypes */
82 int spd_read(uint addr);
86 * This function is reading data from the DIMM module EEPROM over the SPD bus
87 * and uses that to program the sdram controller.
89 * This works on boards that has the same schematics that the AMCC walnut has.
91 * Input: null for default I2C spd functions or a pointer to a custom function
95 long int spd_sdram(int(read_spd)(uint addr))
98 int total_size,bank_size,bank_code;
102 int sdram0_pmit=0x07c00000;
105 #ifndef CONFIG_405EP /* not on PPC405EP */
108 int sdram0_besr0 = -1;
109 int sdram0_besr1 = -1;
110 int sdram0_eccesr = -1;
126 PPC4xx_SYS_INFO sys_info;
127 unsigned long bus_period_x_10;
132 get_sys_info(&sys_info);
133 bus_period_x_10 = ONE_BILLION / (sys_info.freqPLB / 10);
138 * Make sure I2C controller is initialized
141 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
144 /* Make shure we are using SDRAM */
145 if (read_spd(2) != 0x04) {
146 SPD_ERR("SDRAM - non SDRAM memory module found\n");
149 /* ------------------------------------------------------------------
150 * configure memory timing register
153 * 27 IN Row Precharge Time ( t RP)
154 * 29 MIN RAS to CAS Delay ( t RCD)
155 * 127 Component and Clock Detail ,clk0-clk3, junction temp, CAS
156 * -------------------------------------------------------------------*/
159 * first figure out which cas latency mode to use
160 * use the min supported mode
163 tmp = read_spd(127) & 0x6;
164 if (tmp == 0x02) { /* only cas = 2 supported */
166 /* t_ck = read_spd(9); */
167 /* t_ac = read_spd(10); */
168 } else if (tmp == 0x04) { /* only cas = 3 supported */
170 /* t_ck = read_spd(9); */
171 /* t_ac = read_spd(10); */
172 } else if (tmp == 0x06) { /* 2,3 supported, so use 2 */
174 /* t_ck = read_spd(23); */
175 /* t_ac = read_spd(24); */
177 SPD_ERR("SDRAM - unsupported CAS latency \n");
180 /* get some timing values, t_rp,t_rcd,t_ras,t_rc
183 t_rcd = read_spd(29);
184 t_ras = read_spd(30);
187 /* The following timing calcs subtract 1 before deviding.
188 * this has effect of using ceiling instead of floor rounding,
189 * and also subtracting 1 to convert number to reg value
192 sdram0_tr = (min_cas - 1) << SDRAM0_TR_CASL_SHIFT;
194 sdram0_tr |= ((((t_rp - 1) * 10)/bus_period_x_10) & 0x3) << SDRAM0_TR_PTA_SHIFT;
196 tmp = (((t_rc - t_rcd - t_rp -1) * 10) / bus_period_x_10) & 0x3;
199 sdram0_tr |= tmp << SDRAM0_TR_CTP_SHIFT;
200 /* set LDF = 2 cycles, reg value = 1 */
201 sdram0_tr |= 1 << SDRAM0_TR_LDF_SHIFT;
202 /* set RFTA = t_rfc/bus_period, use t_rfc = t_rc */
203 tmp = (((t_rc - 1) * 10) / bus_period_x_10) - 3;
208 sdram0_tr |= tmp << SDRAM0_TR_RFTA_SHIFT;
209 /* set RCD = t_rcd/bus_period*/
210 sdram0_tr |= ((((t_rcd - 1) * 10) / bus_period_x_10) &0x3) << SDRAM0_TR_RCD_SHIFT ;
213 /*------------------------------------------------------------------
214 * configure RTR register
215 * -------------------------------------------------------------------*/
218 tmp = read_spd(12) & 0x7f ; /* refresh type less self refresh bit */
239 SPD_ERR("SDRAM - Bad refresh period \n");
241 /* convert from nsec to bus cycles */
242 tmp = (tmp * 10) / bus_period_x_10;
243 sdram0_rtr = (tmp & 0x3ff8) << SDRAM0_RTR_SHIFT;
245 /*------------------------------------------------------------------
246 * determine the number of banks used
247 * -------------------------------------------------------------------*/
248 /* byte 7:6 is module data width */
249 if (read_spd(7) != 0)
250 SPD_ERR("SDRAM - unsupported module width\n");
253 SPD_ERR("SDRAM - unsupported module width\n");
255 bank_cnt = 1; /* one bank per sdram side */
257 bank_cnt = 2; /* need two banks per side */
259 bank_cnt = 4; /* need four banks per side */
261 SPD_ERR("SDRAM - unsupported module width\n");
263 /* byte 5 is the module row count (refered to as dimm "sides") */
272 bank_cnt = 8; /* 8 is an error code */
274 if (bank_cnt > 4) /* we only have 4 banks to work with */
275 SPD_ERR("SDRAM - unsupported module rows for this width\n");
277 #ifndef CONFIG_405EP /* not on PPC405EP */
278 /* now check for ECC ability of module. We only support ECC
279 * on 32 bit wide devices with 8 bit ECC.
281 if ((read_spd(11)==2) && (read_spd(6)==40) && (read_spd(14)==8)) {
282 sdram0_ecccfg = 0xf << SDRAM0_ECCCFG_SHIFT;
290 /*------------------------------------------------------------------
291 * calculate total size
292 * -------------------------------------------------------------------*/
293 /* calculate total size and do sanity check */
295 total_size = 1 << 22; /* total_size = 4MB */
296 /* now multiply 4M by the smallest device row density */
297 /* note that we don't support asymetric rows */
298 while (((tmp & 0x0001) == 0) && (tmp != 0)) {
299 total_size = total_size << 1;
302 total_size *= read_spd(5); /* mult by module rows (dimm sides) */
304 /*------------------------------------------------------------------
305 * map rows * cols * banks to a mode
306 * -------------------------------------------------------------------*/
319 SPD_ERR("SDRAM - unsupported mode\n");
332 SPD_ERR("SDRAM - unsupported mode\n");
342 if (read_spd(17) == 2)
343 mode = 6; /* mode 7 */
345 mode = 2; /* mode 3 */
348 mode = 2; /* mode 3 */
351 SPD_ERR("SDRAM - unsupported mode\n");
355 SPD_ERR("SDRAM - unsupported mode\n");
358 /*------------------------------------------------------------------
359 * using the calculated values, compute the bank
360 * config register values.
361 * -------------------------------------------------------------------*/
363 /* compute the size of each bank */
364 bank_size = total_size / bank_cnt;
365 /* convert bank size to bank size code for ppc4xx
366 by takeing log2(bank_size) - 22 */
367 tmp = bank_size; /* start with tmp = bank_size */
368 bank_code = 0; /* and bank_code = 0 */
369 while (tmp > 1) { /* this takes log2 of tmp */
370 bank_code++; /* and stores result in bank_code */
372 } /* bank_code is now log2(bank_size) */
373 bank_code -= 22; /* subtract 22 to get the code */
375 tmp = SDRAM0_BXCR_SZ(bank_code) | SDRAM0_BXCR_AM(mode) | 1;
376 sdram0_b0cr = (bank_size * 0) | tmp;
377 #ifndef CONFIG_405EP /* not on PPC405EP */
379 sdram0_b2cr = (bank_size * 1) | tmp;
381 sdram0_b1cr = (bank_size * 2) | tmp;
383 sdram0_b3cr = (bank_size * 3) | tmp;
385 /* PPC405EP chip only supports two SDRAM banks */
387 sdram0_b1cr = (bank_size * 1) | tmp;
389 total_size = 2 * bank_size;
393 * enable sdram controller DCE=1
394 * enable burst read prefetch to 32 bytes BRPF=2
395 * leave other functions off
398 /*------------------------------------------------------------------
399 * now that we've done our calculations, we are ready to
400 * program all the registers.
401 * -------------------------------------------------------------------*/
403 /* disable memcontroller so updates work */
404 mtsdram(SDRAM0_CFG, 0);
406 #ifndef CONFIG_405EP /* not on PPC405EP */
407 mtsdram(SDRAM0_BESR0, sdram0_besr0);
408 mtsdram(SDRAM0_BESR1, sdram0_besr1);
409 mtsdram(SDRAM0_ECCCFG, sdram0_ecccfg);
410 mtsdram(SDRAM0_ECCESR, sdram0_eccesr);
412 mtsdram(SDRAM0_RTR, sdram0_rtr);
413 mtsdram(SDRAM0_PMIT, sdram0_pmit);
414 mtsdram(SDRAM0_B0CR, sdram0_b0cr);
415 mtsdram(SDRAM0_B1CR, sdram0_b1cr);
416 #ifndef CONFIG_405EP /* not on PPC405EP */
417 mtsdram(SDRAM0_B2CR, sdram0_b2cr);
418 mtsdram(SDRAM0_B3CR, sdram0_b3cr);
420 mtsdram(SDRAM0_TR, sdram0_tr);
422 /* SDRAM have a power on delay, 500 micro should do */
424 sdram0_cfg = SDRAM0_CFG_DCE | SDRAM0_CFG_BRPF(1) | SDRAM0_CFG_ECCDD | SDRAM0_CFG_EMDULR;
425 #ifndef CONFIG_405EP /* not on PPC405EP */
427 sdram0_cfg |= SDRAM0_CFG_MEMCHK;
429 mtsdram(SDRAM0_CFG, sdram0_cfg);
434 int spd_read(uint addr)
438 if (i2c_read(SPD_EEPROM_ADDRESS, addr, 1, data, 1) == 0)
444 #endif /* CONFIG_SPD_EEPROM */