summaryrefslogtreecommitdiffstats
path: root/arch/ppc/cpu/ppc4xx/40x_spd_sdram.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/ppc/cpu/ppc4xx/40x_spd_sdram.c')
-rw-r--r--arch/ppc/cpu/ppc4xx/40x_spd_sdram.c464
1 files changed, 464 insertions, 0 deletions
diff --git a/arch/ppc/cpu/ppc4xx/40x_spd_sdram.c b/arch/ppc/cpu/ppc4xx/40x_spd_sdram.c
new file mode 100644
index 0000000..595d568
--- /dev/null
+++ b/arch/ppc/cpu/ppc4xx/40x_spd_sdram.c
@@ -0,0 +1,464 @@
+/*
+ * arch/ppc/cpu/ppc4xx/40x_spd_sdram.c
+ * This SPD SDRAM detection code supports IBM/AMCC PPC44x cpu with a
+ * SDRAM controller. Those are all current 405 PPC's.
+ *
+ * (C) Copyright 2001
+ * Bill Hunter, Wave 7 Optics, williamhunter@attbi.com
+ *
+ * Based on code by:
+ *
+ * Kenneth Johansson ,Ericsson AB.
+ * kenneth.johansson@etx.ericsson.se
+ *
+ * hacked up by bill hunter. fixed so we could run before
+ * serial_init and console_init. previous version avoided this by
+ * running out of cache memory during serial/console init, then running
+ * this code later.
+ *
+ * (C) Copyright 2002
+ * Jun Gu, Artesyn Technology, jung@artesyncp.com
+ * Support for AMCC 440 based on OpenBIOS draminit.c from IBM.
+ *
+ * (C) Copyright 2005
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/processor.h>
+#include <i2c.h>
+#include <ppc4xx.h>
+
+#if defined(CONFIG_SPD_EEPROM) && !defined(CONFIG_440)
+
+/*
+ * Set default values
+ */
+#ifndef CONFIG_SYS_I2C_SPEED
+#define CONFIG_SYS_I2C_SPEED 50000
+#endif
+
+#define ONE_BILLION 1000000000
+
+#define SDRAM0_CFG_DCE 0x80000000
+#define SDRAM0_CFG_SRE 0x40000000
+#define SDRAM0_CFG_PME 0x20000000
+#define SDRAM0_CFG_MEMCHK 0x10000000
+#define SDRAM0_CFG_REGEN 0x08000000
+#define SDRAM0_CFG_ECCDD 0x00400000
+#define SDRAM0_CFG_EMDULR 0x00200000
+#define SDRAM0_CFG_DRW_SHIFT (31-6)
+#define SDRAM0_CFG_BRPF_SHIFT (31-8)
+
+#define SDRAM0_TR_CASL_SHIFT (31-8)
+#define SDRAM0_TR_PTA_SHIFT (31-13)
+#define SDRAM0_TR_CTP_SHIFT (31-15)
+#define SDRAM0_TR_LDF_SHIFT (31-17)
+#define SDRAM0_TR_RFTA_SHIFT (31-29)
+#define SDRAM0_TR_RCD_SHIFT (31-31)
+
+#define SDRAM0_RTR_SHIFT (31-15)
+#define SDRAM0_ECCCFG_SHIFT (31-11)
+
+/* SDRAM0_CFG enable macro */
+#define SDRAM0_CFG_BRPF(x) ( ( x & 0x3)<< SDRAM0_CFG_BRPF_SHIFT )
+
+#define SDRAM0_BXCR_SZ_MASK 0x000e0000
+#define SDRAM0_BXCR_AM_MASK 0x0000e000
+
+#define SDRAM0_BXCR_SZ_SHIFT (31-14)
+#define SDRAM0_BXCR_AM_SHIFT (31-18)
+
+#define SDRAM0_BXCR_SZ(x) ( (( x << SDRAM0_BXCR_SZ_SHIFT) & SDRAM0_BXCR_SZ_MASK) )
+#define SDRAM0_BXCR_AM(x) ( (( x << SDRAM0_BXCR_AM_SHIFT) & SDRAM0_BXCR_AM_MASK) )
+
+#ifdef CONFIG_SPDDRAM_SILENT
+# define SPD_ERR(x) do { return 0; } while (0)
+#else
+# define SPD_ERR(x) do { printf(x); return(0); } while (0)
+#endif
+
+#define sdram_HZ_to_ns(hertz) (1000000000/(hertz))
+
+/* function prototypes */
+int spd_read(uint addr);
+
+
+/*
+ * This function is reading data from the DIMM module EEPROM over the SPD bus
+ * and uses that to program the sdram controller.
+ *
+ * This works on boards that has the same schematics that the AMCC walnut has.
+ *
+ * Input: null for default I2C spd functions or a pointer to a custom function
+ * returning spd_data.
+ */
+
+long int spd_sdram(int(read_spd)(uint addr))
+{
+ int tmp,row,col;
+ int total_size,bank_size,bank_code;
+ int ecc_on;
+ int mode;
+ int bank_cnt;
+
+ int sdram0_pmit=0x07c00000;
+#ifndef CONFIG_405EP /* not on PPC405EP */
+ int sdram0_besr0 = -1;
+ int sdram0_besr1 = -1;
+ int sdram0_eccesr = -1;
+#endif
+ int sdram0_ecccfg;
+
+ int sdram0_rtr=0;
+ int sdram0_tr=0;
+
+ int sdram0_b0cr;
+ int sdram0_b1cr;
+ int sdram0_b2cr;
+ int sdram0_b3cr;
+
+ int sdram0_cfg=0;
+
+ int t_rp;
+ int t_rcd;
+ int t_ras;
+ int t_rc;
+ int min_cas;
+
+ PPC4xx_SYS_INFO sys_info;
+ unsigned long bus_period_x_10;
+
+ /*
+ * get the board info
+ */
+ get_sys_info(&sys_info);
+ bus_period_x_10 = ONE_BILLION / (sys_info.freqPLB / 10);
+
+ if (read_spd == 0){
+ read_spd=spd_read;
+ /*
+ * Make sure I2C controller is initialized
+ * before continuing.
+ */
+ i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+ }
+
+ /* Make shure we are using SDRAM */
+ if (read_spd(2) != 0x04) {
+ SPD_ERR("SDRAM - non SDRAM memory module found\n");
+ }
+
+ /* ------------------------------------------------------------------
+ * configure memory timing register
+ *
+ * data from DIMM:
+ * 27 IN Row Precharge Time ( t RP)
+ * 29 MIN RAS to CAS Delay ( t RCD)
+ * 127 Component and Clock Detail ,clk0-clk3, junction temp, CAS
+ * -------------------------------------------------------------------*/
+
+ /*
+ * first figure out which cas latency mode to use
+ * use the min supported mode
+ */
+
+ tmp = read_spd(127) & 0x6;
+ if (tmp == 0x02) { /* only cas = 2 supported */
+ min_cas = 2;
+/* t_ck = read_spd(9); */
+/* t_ac = read_spd(10); */
+ } else if (tmp == 0x04) { /* only cas = 3 supported */
+ min_cas = 3;
+/* t_ck = read_spd(9); */
+/* t_ac = read_spd(10); */
+ } else if (tmp == 0x06) { /* 2,3 supported, so use 2 */
+ min_cas = 2;
+/* t_ck = read_spd(23); */
+/* t_ac = read_spd(24); */
+ } else {
+ SPD_ERR("SDRAM - unsupported CAS latency \n");
+ }
+
+ /* get some timing values, t_rp,t_rcd,t_ras,t_rc
+ */
+ t_rp = read_spd(27);
+ t_rcd = read_spd(29);
+ t_ras = read_spd(30);
+ t_rc = t_ras + t_rp;
+
+ /* The following timing calcs subtract 1 before deviding.
+ * this has effect of using ceiling instead of floor rounding,
+ * and also subtracting 1 to convert number to reg value
+ */
+ /* set up CASL */
+ sdram0_tr = (min_cas - 1) << SDRAM0_TR_CASL_SHIFT;
+ /* set up PTA */
+ sdram0_tr |= ((((t_rp - 1) * 10)/bus_period_x_10) & 0x3) << SDRAM0_TR_PTA_SHIFT;
+ /* set up CTP */
+ tmp = (((t_rc - t_rcd - t_rp -1) * 10) / bus_period_x_10) & 0x3;
+ if (tmp < 1)
+ tmp = 1;
+ sdram0_tr |= tmp << SDRAM0_TR_CTP_SHIFT;
+ /* set LDF = 2 cycles, reg value = 1 */
+ sdram0_tr |= 1 << SDRAM0_TR_LDF_SHIFT;
+ /* set RFTA = t_rfc/bus_period, use t_rfc = t_rc */
+ tmp = (((t_rc - 1) * 10) / bus_period_x_10) - 3;
+ if (tmp < 0)
+ tmp = 0;
+ if (tmp > 6)
+ tmp = 6;
+ sdram0_tr |= tmp << SDRAM0_TR_RFTA_SHIFT;
+ /* set RCD = t_rcd/bus_period*/
+ sdram0_tr |= ((((t_rcd - 1) * 10) / bus_period_x_10) &0x3) << SDRAM0_TR_RCD_SHIFT ;
+
+
+ /*------------------------------------------------------------------
+ * configure RTR register
+ * -------------------------------------------------------------------*/
+ row = read_spd(3);
+ col = read_spd(4);
+ tmp = read_spd(12) & 0x7f ; /* refresh type less self refresh bit */
+ switch (tmp) {
+ case 0x00:
+ tmp = 15625;
+ break;
+ case 0x01:
+ tmp = 15625 / 4;
+ break;
+ case 0x02:
+ tmp = 15625 / 2;
+ break;
+ case 0x03:
+ tmp = 15625 * 2;
+ break;
+ case 0x04:
+ tmp = 15625 * 4;
+ break;
+ case 0x05:
+ tmp = 15625 * 8;
+ break;
+ default:
+ SPD_ERR("SDRAM - Bad refresh period \n");
+ }
+ /* convert from nsec to bus cycles */
+ tmp = (tmp * 10) / bus_period_x_10;
+ sdram0_rtr = (tmp & 0x3ff8) << SDRAM0_RTR_SHIFT;
+
+ /*------------------------------------------------------------------
+ * determine the number of banks used
+ * -------------------------------------------------------------------*/
+ /* byte 7:6 is module data width */
+ if (read_spd(7) != 0)
+ SPD_ERR("SDRAM - unsupported module width\n");
+ tmp = read_spd(6);
+ if (tmp < 32)
+ SPD_ERR("SDRAM - unsupported module width\n");
+ else if (tmp < 64)
+ bank_cnt = 1; /* one bank per sdram side */
+ else if (tmp < 73)
+ bank_cnt = 2; /* need two banks per side */
+ else if (tmp < 161)
+ bank_cnt = 4; /* need four banks per side */
+ else
+ SPD_ERR("SDRAM - unsupported module width\n");
+
+ /* byte 5 is the module row count (refered to as dimm "sides") */
+ tmp = read_spd(5);
+ if (tmp == 1)
+ ;
+ else if (tmp==2)
+ bank_cnt *= 2;
+ else if (tmp==4)
+ bank_cnt *= 4;
+ else
+ bank_cnt = 8; /* 8 is an error code */
+
+ if (bank_cnt > 4) /* we only have 4 banks to work with */
+ SPD_ERR("SDRAM - unsupported module rows for this width\n");
+
+ /* now check for ECC ability of module. We only support ECC
+ * on 32 bit wide devices with 8 bit ECC.
+ */
+ if ((read_spd(11)==2) && (read_spd(6)==40) && (read_spd(14)==8)) {
+ sdram0_ecccfg = 0xf << SDRAM0_ECCCFG_SHIFT;
+ ecc_on = 1;
+ } else {
+ sdram0_ecccfg = 0;
+ ecc_on = 0;
+ }
+
+ /*------------------------------------------------------------------
+ * calculate total size
+ * -------------------------------------------------------------------*/
+ /* calculate total size and do sanity check */
+ tmp = read_spd(31);
+ total_size = 1 << 22; /* total_size = 4MB */
+ /* now multiply 4M by the smallest device row density */
+ /* note that we don't support asymetric rows */
+ while (((tmp & 0x0001) == 0) && (tmp != 0)) {
+ total_size = total_size << 1;
+ tmp = tmp >> 1;
+ }
+ total_size *= read_spd(5); /* mult by module rows (dimm sides) */
+
+ /*------------------------------------------------------------------
+ * map rows * cols * banks to a mode
+ * -------------------------------------------------------------------*/
+
+ switch (row) {
+ case 11:
+ switch (col) {
+ case 8:
+ mode=4; /* mode 5 */
+ break;
+ case 9:
+ case 10:
+ mode=0; /* mode 1 */
+ break;
+ default:
+ SPD_ERR("SDRAM - unsupported mode\n");
+ }
+ break;
+ case 12:
+ switch (col) {
+ case 8:
+ mode=3; /* mode 4 */
+ break;
+ case 9:
+ case 10:
+ mode=1; /* mode 2 */
+ break;
+ default:
+ SPD_ERR("SDRAM - unsupported mode\n");
+ }
+ break;
+ case 13:
+ switch (col) {
+ case 8:
+ mode=5; /* mode 6 */
+ break;
+ case 9:
+ case 10:
+ if (read_spd(17) == 2)
+ mode = 6; /* mode 7 */
+ else
+ mode = 2; /* mode 3 */
+ break;
+ case 11:
+ mode = 2; /* mode 3 */
+ break;
+ default:
+ SPD_ERR("SDRAM - unsupported mode\n");
+ }
+ break;
+ default:
+ SPD_ERR("SDRAM - unsupported mode\n");
+ }
+
+ /*------------------------------------------------------------------
+ * using the calculated values, compute the bank
+ * config register values.
+ * -------------------------------------------------------------------*/
+ sdram0_b1cr = 0;
+ sdram0_b2cr = 0;
+ sdram0_b3cr = 0;
+
+ /* compute the size of each bank */
+ bank_size = total_size / bank_cnt;
+ /* convert bank size to bank size code for ppc4xx
+ by takeing log2(bank_size) - 22 */
+ tmp = bank_size; /* start with tmp = bank_size */
+ bank_code = 0; /* and bank_code = 0 */
+ while (tmp > 1) { /* this takes log2 of tmp */
+ bank_code++; /* and stores result in bank_code */
+ tmp = tmp >> 1;
+ } /* bank_code is now log2(bank_size) */
+ bank_code -= 22; /* subtract 22 to get the code */
+
+ tmp = SDRAM0_BXCR_SZ(bank_code) | SDRAM0_BXCR_AM(mode) | 1;
+ sdram0_b0cr = (bank_size * 0) | tmp;
+#ifndef CONFIG_405EP /* not on PPC405EP */
+ if (bank_cnt > 1)
+ sdram0_b2cr = (bank_size * 1) | tmp;
+ if (bank_cnt > 2)
+ sdram0_b1cr = (bank_size * 2) | tmp;
+ if (bank_cnt > 3)
+ sdram0_b3cr = (bank_size * 3) | tmp;
+#else
+ /* PPC405EP chip only supports two SDRAM banks */
+ if (bank_cnt > 1)
+ sdram0_b1cr = (bank_size * 1) | tmp;
+ if (bank_cnt > 2)
+ total_size = 2 * bank_size;
+#endif
+
+ /*
+ * enable sdram controller DCE=1
+ * enable burst read prefetch to 32 bytes BRPF=2
+ * leave other functions off
+ */
+
+ /*------------------------------------------------------------------
+ * now that we've done our calculations, we are ready to
+ * program all the registers.
+ * -------------------------------------------------------------------*/
+
+ /* disable memcontroller so updates work */
+ mtsdram(SDRAM0_CFG, 0);
+
+#ifndef CONFIG_405EP /* not on PPC405EP */
+ mtsdram(SDRAM0_BESR0, sdram0_besr0);
+ mtsdram(SDRAM0_BESR1, sdram0_besr1);
+ mtsdram(SDRAM0_ECCCFG, sdram0_ecccfg);
+ mtsdram(SDRAM0_ECCESR, sdram0_eccesr);
+#endif
+ mtsdram(SDRAM0_RTR, sdram0_rtr);
+ mtsdram(SDRAM0_PMIT, sdram0_pmit);
+ mtsdram(SDRAM0_B0CR, sdram0_b0cr);
+ mtsdram(SDRAM0_B1CR, sdram0_b1cr);
+#ifndef CONFIG_405EP /* not on PPC405EP */
+ mtsdram(SDRAM0_B2CR, sdram0_b2cr);
+ mtsdram(SDRAM0_B3CR, sdram0_b3cr);
+#endif
+ mtsdram(SDRAM0_TR, sdram0_tr);
+
+ /* SDRAM have a power on delay, 500 micro should do */
+ udelay(500);
+ sdram0_cfg = SDRAM0_CFG_DCE | SDRAM0_CFG_BRPF(1) | SDRAM0_CFG_ECCDD | SDRAM0_CFG_EMDULR;
+ if (ecc_on)
+ sdram0_cfg |= SDRAM0_CFG_MEMCHK;
+ mtsdram(SDRAM0_CFG, sdram0_cfg);
+
+ return (total_size);
+}
+
+int spd_read(uint addr)
+{
+ uchar data[2];
+
+ if (i2c_read(SPD_EEPROM_ADDRESS, addr, 1, data, 1) == 0)
+ return (int)data[0];
+ else
+ return 0;
+}
+
+#endif /* CONFIG_SPD_EEPROM */