From 026457a98c2057dc5d6a8533cab0a8c5aea374d6 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Sat, 18 Feb 2012 18:12:14 +0100
Subject: [PATCH] Send SDRAM initialization sequence and answer PHY read/write
 requests. Obstinately refuses to work, unfortunately.

---
 milkymist/dfii/__init__.py |  7 +++-
 software/bios/ddrinit.c    | 75 ++++++++++++++++++++++++++++++++++++--
 top.py                     |  2 +-
 3 files changed, 79 insertions(+), 5 deletions(-)

diff --git a/milkymist/dfii/__init__.py b/milkymist/dfii/__init__.py
index 42926200..c8dfbbe8 100644
--- a/milkymist/dfii/__init__.py
+++ b/milkymist/dfii/__init__.py
@@ -83,7 +83,6 @@ class DFIInjector:
 				phase.we_n.eq(1),
 				phase.cas_n.eq(1),
 				phase.ras_n.eq(1)
-				
 			]
 		
 		# commands
@@ -101,6 +100,12 @@ class DFIInjector:
 			)
 		]
 		
+		# addresses
+		comb += [
+			cmdphase.address.eq(self._address.field.r),
+			cmdphase.bank.eq(self._baddress.field.r)
+		]
+		
 		# data enables
 		sync += _data_en(self._command.re & self._rddata.r,
 			rddata_en,
diff --git a/software/bios/ddrinit.c b/software/bios/ddrinit.c
index 24352a7c..5edce234 100644
--- a/software/bios/ddrinit.c
+++ b/software/bios/ddrinit.c
@@ -18,13 +18,65 @@
 #include <stdio.h>
 
 #include <hw/s6ddrphy.h>
+#include <hw/dfii.h>
 
 #include "ddrinit.h"
 
+static void cdelay(int i)
+{
+	while(i > 0) {
+		__asm__ volatile("nop");
+		i--;
+	}
+}
+
+static void setaddr(int a)
+{
+	CSR_DFII_AH = (a & 0x1fe0) >> 5;
+	CSR_DFII_AL = a & 0x001f;
+}
+
 static void init_sequence(void)
 {
+	int i;
+	
 	printf("Sending initialization sequence...\n");
-	// TODO
+	
+	/* Bring CKE high */
+	setaddr(0x0000);
+	CSR_DFII_BA = 0;
+	CSR_DFII_CONTROL = DFII_CONTROL_CKE;
+	
+	/* Precharge All */
+	setaddr(0x0400);
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
+	
+	/* Load Extended Mode Register */
+	CSR_DFII_BA = 1;
+	setaddr(0x0000);
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_CAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
+	CSR_DFII_BA = 0;
+	
+	/* Load Mode Register */
+	setaddr(0x0132); /* Reset DLL, CL=3, BL=4 */
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_CAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
+	cdelay(200);
+	
+	/* Precharge All */
+	setaddr(0x0400);
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
+	
+	/* 2x Auto Refresh */
+	for(i=0;i<2;i++) {
+		setaddr(0);
+		CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_CAS|DFII_COMMAND_CS;
+		cdelay(4);
+	}
+	
+	/* Load Mode Register */
+	setaddr(0x0032); /* CL=3, BL=4 */
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_CAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
+	cdelay(200);
 }
 
 static void calibrate_phy(void)
@@ -33,21 +85,38 @@ static void calibrate_phy(void)
 	int addr;
 	
 	printf("Calibrating PHY...\n");
+	
+	CSR_DFII_WRDELAY = 4;
+	CSR_DFII_WRDURATION = 1;
+	CSR_DFII_RDDELAY = 7;
+	CSR_DFII_RDDURATION = 1;
+	
+	/* Use bank 0, activate row 0 */
+	CSR_DFII_BA = 0;
+	setaddr(0x0000);
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_CS;
+	
 	while(!(CSR_DDRPHY_STATUS & DDRPHY_STATUS_PHY_CAL_DONE)) {
+		cdelay(20);
 		requests = CSR_DDRPHY_REQUESTS;
 		addr = CSR_DDRPHY_REQADDR;
 		
+		setaddr(addr << 2);
 		if(requests & DDRPHY_REQUEST_READ) {
 			printf("R %d\n", addr);
-			// TODO
+			CSR_DFII_COMMAND = DFII_COMMAND_RDDATA|DFII_COMMAND_CAS|DFII_COMMAND_CS;
 		}
 		if(requests & DDRPHY_REQUEST_WRITE) {
 			printf("W %d\n", addr);
-			// TODO
+			CSR_DFII_COMMAND = DFII_COMMAND_WRDATA|DFII_COMMAND_CAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
 		}
 		
 		CSR_DDRPHY_REQUESTS = requests;
 	}
+	
+	/* Precharge All */
+	setaddr(0x0400);
+	CSR_DFII_COMMAND = DFII_COMMAND_RAS|DFII_COMMAND_WE|DFII_COMMAND_CS;
 }
 
 int ddrinit(void)
diff --git a/top.py b/top.py
index 3e97119d..47367406 100644
--- a/top.py
+++ b/top.py
@@ -43,7 +43,7 @@ def get():
 	# DFI
 	#
 	ddrphy0 = s6ddrphy.S6DDRPHY(1, dfi_a, dfi_ba, dfi_d)
-	dfii0 = dfii.DFIInjector(2, dfi_a, dfi_ba, dfi_d, 2)
+	dfii0 = dfii.DFIInjector(2, dfi_a, dfi_ba, dfi_d, 1)
 	dficon0 = dfi.Interconnect(dfii0.master, ddrphy0.dfi)
 
 	#
-- 
2.30.2