Copy 440EPx/GRx SDRAM data-eye search to common directory

This patch creates a non-board-specific file for performing the SDRAM
data-eye search.  It also adds ECC error checking to the test of valid
data on readback when ECC is enabled.

Signed-off-by: Larry Johnson <lrj@acm.org>

cpu/ppc4xx/denali_data_eye.c

+/*
+ * cpu/ppc4xx/denali_data_eye.c
+ * Extracted from board/amcc/sequoia/sdram.c by Larry Johnson <lrj@acm.org>.
+ *
+ * (C) Copyright 2006
+ * Sylvie Gohl,             AMCC/IBM, gohl.sylvie@fr.ibm.com
+ * Jacqueline Pira-Ferriol, AMCC/IBM, jpira-ferriol@fr.ibm.com
+ * Thierry Roman,           AMCC/IBM, thierry_roman@fr.ibm.com
+ * Alain Saurel,            AMCC/IBM, alain.saurel@fr.ibm.com
+ * Robert Snyder,           AMCC/IBM, rob.snyder@fr.ibm.com
+ *
+ * (C) Copyright 2006-2007
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * 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
+ */
+
+/* define DEBUG for debugging output (obviously ;-)) */
+#if 0
+#define DEBUG
+#endif
+
+#include <common.h>
+#include <asm/processor.h>
+#include <asm/io.h>
+#include <ppc4xx.h>
+
+#if defined(CONFIG_440EPX) || defined(CONFIG_440GRX)
+/*-----------------------------------------------------------------------------+
+ * denali_wait_for_dlllock.
+ +----------------------------------------------------------------------------*/
+int denali_wait_for_dlllock(void)
+{
+	u32 val;
+	int wait;
+
+	/* -----------------------------------------------------------+
+	 * Wait for the DCC master delay line to finish calibration
+	 * ----------------------------------------------------------*/
+	for (wait = 0; wait != 0xffff; ++wait) {
+		mfsdram(DDR0_17, val);
+		if (DDR0_17_DLLLOCKREG_DECODE(val)) {
+			/* dlllockreg bit on */
+			return 0;
+		}
+	}
+	debug("0x%04x: DDR0_17 Value (dlllockreg bit): 0x%08x\n", wait, val);
+	debug("Waiting for dlllockreg bit to raise\n");
+	return -1;
+}
+
+#if defined(CONFIG_DDR_DATA_EYE)
+#define DDR_DCR_BASE 0x10
+#define ddrcfga  (DDR_DCR_BASE+0x0)	/* DDR configuration address reg */
+#define ddrcfgd  (DDR_DCR_BASE+0x1)	/* DDR configuration data reg    */
+
+/*-----------------------------------------------------------------------------+
+ * wait_for_dram_init_complete.
+ +----------------------------------------------------------------------------*/
+static int wait_for_dram_init_complete(void)
+{
+	unsigned long val;
+	int wait = 0;
+
+	/* --------------------------------------------------------------+
+	 * Wait for 'DRAM initialization complete' bit in status register
+	 * -------------------------------------------------------------*/
+	mtdcr(ddrcfga, DDR0_00);
+
+	while (wait != 0xffff) {
+		val = mfdcr(ddrcfgd);
+		if ((val & DDR0_00_INT_STATUS_BIT6) == DDR0_00_INT_STATUS_BIT6)
+			/* 'DRAM initialization complete' bit */
+			return 0;
+		else
+			wait++;
+	}
+	debug("DRAM initialization complete bit in status register did not "
+	      "rise\n");
+	return -1;
+}
+
+#define NUM_TRIES 64
+#define NUM_READS 10
+
+/*-----------------------------------------------------------------------------+
+ * denali_core_search_data_eye.
+ +----------------------------------------------------------------------------*/
+/*
+ * Avoid conflict with implementations of denali_core_search_data_eye in board-
+ * specific code.
+ */
+void denali_core_search_data_eye(void)
+    __attribute__ ((weak, alias("__denali_core_search_data_eye")));
+
+void __denali_core_search_data_eye(void)
+{
+	int k, j;
+	u32 val;
+	u32 wr_dqs_shift, dqs_out_shift, dll_dqs_delay_X;
+	u32 max_passing_cases = 0, wr_dqs_shift_with_max_passing_cases = 0;
+	u32 passing_cases = 0, dll_dqs_delay_X_sw_val = 0;
+	u32 dll_dqs_delay_X_start_window = 0, dll_dqs_delay_X_end_window = 0;
+	volatile u32 *ram_pointer;
+	u32 test[NUM_TRIES] = {
+		0x00000000, 0x00000000, 0xFFFFFFFF, 0xFFFFFFFF,
+		0x00000000, 0x00000000, 0xFFFFFFFF, 0xFFFFFFFF,
+		0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0x00000000,
+		0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0x00000000,
+		0xAAAAAAAA, 0xAAAAAAAA, 0x55555555, 0x55555555,
+		0xAAAAAAAA, 0xAAAAAAAA, 0x55555555, 0x55555555,
+		0x55555555, 0x55555555, 0xAAAAAAAA, 0xAAAAAAAA,
+		0x55555555, 0x55555555, 0xAAAAAAAA, 0xAAAAAAAA,
+		0xA5A5A5A5, 0xA5A5A5A5, 0x5A5A5A5A, 0x5A5A5A5A,
+		0xA5A5A5A5, 0xA5A5A5A5, 0x5A5A5A5A, 0x5A5A5A5A,
+		0x5A5A5A5A, 0x5A5A5A5A, 0xA5A5A5A5, 0xA5A5A5A5,
+		0x5A5A5A5A, 0x5A5A5A5A, 0xA5A5A5A5, 0xA5A5A5A5,
+		0xAA55AA55, 0xAA55AA55, 0x55AA55AA, 0x55AA55AA,
+		0xAA55AA55, 0xAA55AA55, 0x55AA55AA, 0x55AA55AA,
+		0x55AA55AA, 0x55AA55AA, 0xAA55AA55, 0xAA55AA55,
+		0x55AA55AA, 0x55AA55AA, 0xAA55AA55, 0xAA55AA55
+	};
+
+	ram_pointer = (volatile u32 *)(CFG_SDRAM_BASE);
+
+	for (wr_dqs_shift = 64; wr_dqs_shift < 96; wr_dqs_shift++) {
+		/* for (wr_dqs_shift=1; wr_dqs_shift<96; wr_dqs_shift++) { */
+
+		/* -----------------------------------------------------------+
+		 * De-assert 'start' parameter.
+		 * ----------------------------------------------------------*/
+		mtdcr(ddrcfga, DDR0_02);
+		val = (mfdcr(ddrcfgd) & ~DDR0_02_START_MASK) |
+		    DDR0_02_START_OFF;
+		mtdcr(ddrcfgd, val);
+
+		/* -----------------------------------------------------------+
+		 * Set 'wr_dqs_shift'
+		 * ----------------------------------------------------------*/
+		mtdcr(ddrcfga, DDR0_09);
+		val = (mfdcr(ddrcfgd) & ~DDR0_09_WR_DQS_SHIFT_MASK) |
+		    DDR0_09_WR_DQS_SHIFT_ENCODE(wr_dqs_shift);
+		mtdcr(ddrcfgd, val);
+
+		/* -----------------------------------------------------------+
+		 * Set 'dqs_out_shift' = wr_dqs_shift + 32
+		 * ----------------------------------------------------------*/
+		dqs_out_shift = wr_dqs_shift + 32;
+		mtdcr(ddrcfga, DDR0_22);
+		val = (mfdcr(ddrcfgd) & ~DDR0_22_DQS_OUT_SHIFT_MASK) |
+		    DDR0_22_DQS_OUT_SHIFT_ENCODE(dqs_out_shift);
+		mtdcr(ddrcfgd, val);
+
+		passing_cases = 0;
+
+		for (dll_dqs_delay_X = 1; dll_dqs_delay_X < 64;
+		     dll_dqs_delay_X++) {
+			/* for (dll_dqs_delay_X=1; dll_dqs_delay_X<128;
+			   dll_dqs_delay_X++) { */
+			/* -----------------------------------------------------------+
+			 * Set 'dll_dqs_delay_X'.
+			 * ----------------------------------------------------------*/
+			/* dll_dqs_delay_0 */
+			mtdcr(ddrcfga, DDR0_17);
+			val = (mfdcr(ddrcfgd) & ~DDR0_17_DLL_DQS_DELAY_0_MASK)
+			    | DDR0_17_DLL_DQS_DELAY_0_ENCODE(dll_dqs_delay_X);
+			mtdcr(ddrcfgd, val);
+			/* dll_dqs_delay_1 to dll_dqs_delay_4 */
+			mtdcr(ddrcfga, DDR0_18);
+			val = (mfdcr(ddrcfgd) & ~DDR0_18_DLL_DQS_DELAY_X_MASK)
+			    | DDR0_18_DLL_DQS_DELAY_4_ENCODE(dll_dqs_delay_X)
+			    | DDR0_18_DLL_DQS_DELAY_3_ENCODE(dll_dqs_delay_X)
+			    | DDR0_18_DLL_DQS_DELAY_2_ENCODE(dll_dqs_delay_X)
+			    | DDR0_18_DLL_DQS_DELAY_1_ENCODE(dll_dqs_delay_X);
+			mtdcr(ddrcfgd, val);
+			/* dll_dqs_delay_5 to dll_dqs_delay_8 */
+			mtdcr(ddrcfga, DDR0_19);
+			val = (mfdcr(ddrcfgd) & ~DDR0_19_DLL_DQS_DELAY_X_MASK)
+			    | DDR0_19_DLL_DQS_DELAY_8_ENCODE(dll_dqs_delay_X)
+			    | DDR0_19_DLL_DQS_DELAY_7_ENCODE(dll_dqs_delay_X)
+			    | DDR0_19_DLL_DQS_DELAY_6_ENCODE(dll_dqs_delay_X)
+			    | DDR0_19_DLL_DQS_DELAY_5_ENCODE(dll_dqs_delay_X);
+			mtdcr(ddrcfgd, val);
+			/* clear any ECC errors */
+			mtdcr(ddrcfga, DDR0_00);
+			mtdcr(ddrcfgd,
+			      mfdcr(ddrcfgd) | DDR0_00_INT_ACK_ENCODE(0x3C));
+
+			sync();
+			eieio();
+
+			/* -----------------------------------------------------------+
+			 * Assert 'start' parameter.
+			 * ----------------------------------------------------------*/
+			mtdcr(ddrcfga, DDR0_02);
+			val = (mfdcr(ddrcfgd) & ~DDR0_02_START_MASK) |
+			    DDR0_02_START_ON;
+			mtdcr(ddrcfgd, val);
+
+			sync();
+			eieio();
+
+			/* -----------------------------------------------------------+
+			 * Wait for the DCC master delay line to finish calibration
+			 * ----------------------------------------------------------*/
+			if (denali_wait_for_dlllock() != 0) {
+				printf("dll lock did not occur !!!\n");
+				printf("denali_core_search_data_eye!!!\n");
+				printf("wr_dqs_shift = %d - dll_dqs_delay_X = "
+				       "%d\n", wr_dqs_shift, dll_dqs_delay_X);
+				hang();
+			}
+			sync();
+			eieio();
+
+			if (wait_for_dram_init_complete() != 0) {
+				printf("dram init complete did not occur!!!\n");
+				printf("denali_core_search_data_eye!!!\n");
+				printf("wr_dqs_shift = %d - dll_dqs_delay_X = "
+				       "%d\n", wr_dqs_shift, dll_dqs_delay_X);
+				hang();
+			}
+			udelay(100); /* wait 100us to ensure init is really completed !!! */
+
+			/* write values */
+			for (j = 0; j < NUM_TRIES; j++) {
+				ram_pointer[j] = test[j];
+
+				/* clear any cache at ram location */
+			      __asm__("dcbf 0,%0": :"r"(&ram_pointer[j]));
+			}
+
+			/* read values back */
+			for (j = 0; j < NUM_TRIES; j++) {
+				for (k = 0; k < NUM_READS; k++) {
+					/* clear any cache at ram location */
+				      __asm__("dcbf 0,%0": :"r"(&ram_pointer
+					    [j]));
+
+					if (ram_pointer[j] != test[j])
+						break;
+				}
+
+				/* read error */
+				if (k != NUM_READS)
+					break;
+			}
+
+			/* See if the dll_dqs_delay_X value passed. */
+			mtdcr(ddrcfga, DDR0_00);
+			if (j < NUM_TRIES
+			    || (DDR0_00_INT_STATUS_DECODE(mfdcr(ddrcfgd)) &
+				0x3F)) {
+				/* Failed */
+				passing_cases = 0;
+				/* break; */
+			} else {
+				/* Passed */
+				if (passing_cases == 0)
+					dll_dqs_delay_X_sw_val =
+					    dll_dqs_delay_X;
+				passing_cases++;
+				if (passing_cases >= max_passing_cases) {
+					max_passing_cases = passing_cases;
+					wr_dqs_shift_with_max_passing_cases =
+					    wr_dqs_shift;
+					dll_dqs_delay_X_start_window =
+					    dll_dqs_delay_X_sw_val;
+					dll_dqs_delay_X_end_window =
+					    dll_dqs_delay_X;
+				}
+			}
+
+			/* -----------------------------------------------------------+
+			 * De-assert 'start' parameter.
+			 * ----------------------------------------------------------*/
+			mtdcr(ddrcfga, DDR0_02);
+			val = (mfdcr(ddrcfgd) & ~DDR0_02_START_MASK) |
+			    DDR0_02_START_OFF;
+			mtdcr(ddrcfgd, val);
+		} /* for (dll_dqs_delay_X=0; dll_dqs_delay_X<128; dll_dqs_delay_X++) */
+	} /* for (wr_dqs_shift=0; wr_dqs_shift<96; wr_dqs_shift++) */
+
+	/* -----------------------------------------------------------+
+	 * Largest passing window is now detected.
+	 * ----------------------------------------------------------*/
+
+	/* Compute dll_dqs_delay_X value */
+	dll_dqs_delay_X = (dll_dqs_delay_X_end_window +
+			   dll_dqs_delay_X_start_window) / 2;
+	wr_dqs_shift = wr_dqs_shift_with_max_passing_cases;
+
+	debug("DQS calibration - Window detected:\n");
+	debug("max_passing_cases = %d\n", max_passing_cases);
+	debug("wr_dqs_shift      = %d\n", wr_dqs_shift);
+	debug("dll_dqs_delay_X   = %d\n", dll_dqs_delay_X);
+	debug("dll_dqs_delay_X window = %d - %d\n",
+	      dll_dqs_delay_X_start_window, dll_dqs_delay_X_end_window);
+
+	/* -----------------------------------------------------------+
+	 * De-assert 'start' parameter.
+	 * ----------------------------------------------------------*/
+	mtdcr(ddrcfga, DDR0_02);
+	val = (mfdcr(ddrcfgd) & ~DDR0_02_START_MASK) | DDR0_02_START_OFF;
+	mtdcr(ddrcfgd, val);
+
+	/* -----------------------------------------------------------+
+	 * Set 'wr_dqs_shift'
+	 * ----------------------------------------------------------*/
+	mtdcr(ddrcfga, DDR0_09);
+	val = (mfdcr(ddrcfgd) & ~DDR0_09_WR_DQS_SHIFT_MASK)
+	    | DDR0_09_WR_DQS_SHIFT_ENCODE(wr_dqs_shift);
+	mtdcr(ddrcfgd, val);
+	debug("DDR0_09=0x%08lx\n", val);
+
+	/* -----------------------------------------------------------+
+	 * Set 'dqs_out_shift' = wr_dqs_shift + 32
+	 * ----------------------------------------------------------*/
+	dqs_out_shift = wr_dqs_shift + 32;
+	mtdcr(ddrcfga, DDR0_22);
+	val = (mfdcr(ddrcfgd) & ~DDR0_22_DQS_OUT_SHIFT_MASK)
+	    | DDR0_22_DQS_OUT_SHIFT_ENCODE(dqs_out_shift);
+	mtdcr(ddrcfgd, val);
+	debug("DDR0_22=0x%08lx\n", val);
+
+	/* -----------------------------------------------------------+
+	 * Set 'dll_dqs_delay_X'.
+	 * ----------------------------------------------------------*/
+	/* dll_dqs_delay_0 */
+	mtdcr(ddrcfga, DDR0_17);
+	val = (mfdcr(ddrcfgd) & ~DDR0_17_DLL_DQS_DELAY_0_MASK)
+	    | DDR0_17_DLL_DQS_DELAY_0_ENCODE(dll_dqs_delay_X);
+	mtdcr(ddrcfgd, val);
+	debug("DDR0_17=0x%08lx\n", val);
+
+	/* dll_dqs_delay_1 to dll_dqs_delay_4 */
+	mtdcr(ddrcfga, DDR0_18);
+	val = (mfdcr(ddrcfgd) & ~DDR0_18_DLL_DQS_DELAY_X_MASK)
+	    | DDR0_18_DLL_DQS_DELAY_4_ENCODE(dll_dqs_delay_X)
+	    | DDR0_18_DLL_DQS_DELAY_3_ENCODE(dll_dqs_delay_X)
+	    | DDR0_18_DLL_DQS_DELAY_2_ENCODE(dll_dqs_delay_X)
+	    | DDR0_18_DLL_DQS_DELAY_1_ENCODE(dll_dqs_delay_X);
+	mtdcr(ddrcfgd, val);
+	debug("DDR0_18=0x%08lx\n", val);
+
+	/* dll_dqs_delay_5 to dll_dqs_delay_8 */
+	mtdcr(ddrcfga, DDR0_19);
+	val = (mfdcr(ddrcfgd) & ~DDR0_19_DLL_DQS_DELAY_X_MASK)
+	    | DDR0_19_DLL_DQS_DELAY_8_ENCODE(dll_dqs_delay_X)
+	    | DDR0_19_DLL_DQS_DELAY_7_ENCODE(dll_dqs_delay_X)
+	    | DDR0_19_DLL_DQS_DELAY_6_ENCODE(dll_dqs_delay_X)
+	    | DDR0_19_DLL_DQS_DELAY_5_ENCODE(dll_dqs_delay_X);
+	mtdcr(ddrcfgd, val);
+	debug("DDR0_19=0x%08lx\n", val);
+
+	/* -----------------------------------------------------------+
+	 * Assert 'start' parameter.
+	 * ----------------------------------------------------------*/
+	mtdcr(ddrcfga, DDR0_02);
+	val = (mfdcr(ddrcfgd) & ~DDR0_02_START_MASK) | DDR0_02_START_ON;
+	mtdcr(ddrcfgd, val);
+
+	sync();
+	eieio();
+
+	/* -----------------------------------------------------------+
+	 * Wait for the DCC master delay line to finish calibration
+	 * ----------------------------------------------------------*/
+	if (denali_wait_for_dlllock() != 0) {
+		printf("dll lock did not occur !!!\n");
+		hang();
+	}
+	sync();
+	eieio();
+
+	if (wait_for_dram_init_complete() != 0) {
+		printf("dram init complete did not occur !!!\n");
+		hang();
+	}
+	udelay(100); /* wait 100us to ensure init is really completed !!! */
+}
+#endif /* defined(CONFIG_DDR_DATA_EYE) */
+#endif /* defined(CONFIG_440EPX) || defined(CONFIG_440GRX) */