just to get us back where we were.

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1151 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 239 insertions, 12 deletions

diff --git a/src/northbridge/via/vt8601/raminit.c b/src/northbridge/via/vt8601/raminit.c
index 864fbbe282..58723091b6 100644
--- a/src/northbridge/via/vt8601/raminit.c
+++ b/src/northbridge/via/vt8601/raminit.c
@@ -33,18 +33,6 @@ it with the version available from LANL.
  * 5/19/03 by SONE Takeshi <ts1@tsn.or.jp>
  */
 
-// Set to 1 if your DIMMs are PC133
-// Note that I'm assuming CPU's FSB frequency is 133MHz. If your CPU runs
-// at another bus speed, you might need to change some of register values.
-#ifndef DIMM_PC133
-#define DIMM_PC133 0
-#endif
-
-// Set to 1 if your DIMMs are CL=2
-#ifndef DIMM_CL2
-#define DIMM_CL2 0
-#endif
-
 
 /* Stable ~1 usec delay by hitting unused ISA port. */
 #define UDELAY(x) movl $x,%ecx; 9: outb %al,$0x81; loop 9b
@@ -310,7 +298,246 @@ msg_bytes:
         .previous
 #endif
 
+	/* this is an early hack. We're going to just try to get memory
+	 * working as it was before. I need help for SPD! RGM
+	 */
+// Set to 1 if your DIMMs are PC133
+// Note that I'm assuming CPU's FSB frequency is 133MHz. If your CPU runs
+// at another bus speed, you might need to change some of register values.
+#ifndef DIMM_PC133
+#define DIMM_PC133 0
+#endif
+
+// Set to 1 if your DIMMs are CL=2
+#ifndef DIMM_CL2
+#define DIMM_CL2 0
+#endif
+/* Stable ~1 usec delay by hitting unused ISA port. */
+#define UDELAY(x) movl $x,%ecx; 9: outb %al,$0x81; loop 9b
+
+	  void dimms_read(unsigned long x) {
+	  unsigned long eax; 
+	  volatile unsigned long y;
+	  eax =  x;
+	  for(; eax < 0x60000000; eax += 0x10000000)
+	    y = * (volatile unsigned long *) eax;
+}
+	  void dimms_write(int x) {
+	  unsigned long eax = x;
+	  for(; eax < 0x60000000; eax += 0x10000000)
+	    *(volatile unsigned long *) eax = 0;
+}
+
 static void sdram_set_registers(const struct mem_controller *ctrl) {
+static const uint16_t raminit_ma_reg_table[] = {
+  /* Values for MA type register to try */
+  0x0000, 0x8088, 0xe0ee,
+  0xffff // end mark
+};
+
+	device_t north = 0;
+  uint8_t c, r;
+
+  	print_err("vt8601 init starting\n");
+	north = pci_locate_device(PCI_ID(0x1106, 0x8601), north);
+	print_err_hex32(north);
+	print_err(" is the north\n");
+	// memory clk enable. We are not using ECC
+	pci_write_config8(north,0x78, 0x01);
+	// dram control, see the book. 
+#if DIMM_PC133
+	pci_write_config8(north,0x68, 0x52);
+#else
+        pci_write_config8(north,0x68, 0x42);
+#endif
+	// dram control, see the book. 
+	pci_write_config8(north,0x6B, 0x0c);
+	// Initial setting, 256MB in each bank, will be rewritten later.
+	pci_write_config8(north,0x5A, 0x20);
+	pci_write_config8(north,0x5B, 0x40);
+	pci_write_config8(north,0x5C, 0x60);
+	pci_write_config8(north,0x5D, 0x80);
+	pci_write_config8(north,0x5E, 0xA0);
+	pci_write_config8(north,0x5F, 0xC0);
+        // It seems we have to take care of these 2 registers as if 
+        // they are bank 6 and 7.
+        pci_write_config8(north,0x56, 0xC0);
+        pci_write_config8(north,0x57, 0xC0);
+
+	// SDRAM in all banks
+	pci_write_config8(north,0x60, 0x3F);
+	// DRAM timing. I'm suspicious of this
+	// This is for all banks, 64 is 0,1.  65 is 2,3. 66 is 4,5.
+	// ras precharge 4T, RAS pulse 5T
+	// cas2 is 0xd6, cas3 is 0xe6
+	// we're also backing off write pulse width to 2T, so result is 0xee
+#if DIMM_CL2
+	pci_write_config8(north,0x64, 0xd4);
+	pci_write_config8(north,0x65, 0xd4);
+	pci_write_config8(north,0x66, 0xd4);
+#else // CL=3
+	pci_write_config8(north,0x64, 0xe4);
+	pci_write_config8(north,0x65, 0xe4);
+	pci_write_config8(north,0x66, 0xe4);
+#endif
+
+	// dram frequency select.
+	// enable 4K pages for 64M dram. 
+#if DIMM_PC133
+	pci_write_config8(north,0x69, 0x3c);
+#else
+        pci_write_config8(north,0x69, 0xac);
+#endif
+	// refresh counter, disabled.
+	pci_write_config8(north,0x6A, 0x00);
+	// clkenable configuration. kevinh FIXME - add precharge
+	pci_write_config8(north,0x6C, 0x00);
+	// dram read latch delay of 1 ns, MD drive 8 mA,
+	// high drive strength on MA[2:	13], we#, cas#, ras#
+	// As per Cindy Lee, set to 0x37, not 0x57
+	pci_write_config8(north,0x6D, 0x7f);
+
+        /* Initialize all banks at once */
+
+/* begin to initialize*/
+	// I forget why we need this, but we do
+	  dimms_write(0xa55a5aa5);
+
+/* set NOP*/
+	pci_write_config8(north,0x6C, 0x01);
+
+/* wait 200us*/
+	// You need to do the memory reference. That causes the nop cycle. 
+	  dimms_read(0);
+	udelay(400);
+
+/* set precharge */
+	pci_write_config8(north,0x6C, 0x02);
+
+/* dummy reads*/
+	  dimms_read(0);
+	udelay(200);
+
+/* set CBR*/
+	pci_write_config8(north,0x6C, 0x04);
+	
+/* do 8 reads and wait >100us between each - from via*/
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+        dimms_read(0);
+	udelay(200);
+
+/* set MRS*/
+	pci_write_config8(north,0x6c, 0x03);
+#if DIMM_CL2
+        dimms_read(0x150);
+#else // CL=3
+        dimms_read(0x1d0);
+#endif
+	udelay(200);
+
+/* set to normal mode */
+	pci_write_config8(north,0x6C, 0x08);
+
+	  dimms_write(0x55aa55aa);
+        dimms_read(0);
+	udelay(200);
+
+	// Set the refresh rate. 
+#if DIMM_PC133
+	pci_write_config8(north,0x6A, 0x86);
+#else
+	pci_write_config8(north,0x6A, 0x65);
+#endif
+	// enable multi-page open
+	pci_write_config8(north,0x6B, 0x0d);
+
+        /* Begin auto-detection
+         * Find the first bank with DIMM equipped. */
+
+        /* Maximum possible memory in bank 0, none in other banks.
+         * Starting from bank 0, we's fill 0 in these registers
+         * until memory is found. */
+	pci_write_config8(north,0x5A, 0xff);
+	pci_write_config8(north,0x5B, 0xff);
+	pci_write_config8(north,0x5C, 0xff);
+	pci_write_config8(north,0x5D, 0xff);
+	pci_write_config8(north,0x5E, 0xff);
+	pci_write_config8(north,0x5F, 0xff);
+	pci_write_config8(north,0x56, 0xff);
+	pci_write_config8(north,0x57, 0xff);
+
+	  /* this code is broken ... ignores 56, 57 */
+	  for(c = 0x5a; c < 0x60; c++) {
+        /* Write different values to 0 and 8, then read from 0.
+         * If values of address 0 match, we have something there. */
+	    *(volatile unsigned long *) 0 = 0x12345678;
+
+	    /* LEAVE THIS HERE. IT IS ESSENTIAL. OTHERWISE BUFFERING
+	     * WILL FOOL YOU!
+	     */
+	    *(volatile unsigned long *) 8 = 0x87654321;
+	    if (*(volatile unsigned long *) 0 != 0x12345678) {
+
+	      /* No memory in this bank. Tell it to the bridge. */
+	      pci_write_config8(north,c, 0);
+		} else {
+		    uint8_t best = 0;
+
+        /* Detect MA mapping type of the first bank. */
+
+		  for(r = 0; r < 3; r++) {
+		    volatile unsigned long esi = 0;
+		    volatile unsigned long eax = 0;
+		    pci_write_config8(north,0x58, raminit_ma_reg_table[r]);
+		    * (volatile unsigned long *) eax = 0;
+		    // Write to addresses with only one address bit
+		    // on, from 0x80000000 to 0x00000008 (lower 3 bits
+		    // are ignored, assuming 64-bit bus).  Then what
+		    // is read at address 0 is the value written to
+		    // the lowest address where it gets
+		    // wrap-around. That address is either the size of
+		    // the bank, or a missing bit due to incorrect MA
+		    // mapping.
+		    eax = 0x80000000;
+		    while (eax !=  4) {
+		      eax = * (volatile unsigned long *) eax;
+		      eax >>= 1;
+		    }
+		    eax = 0;
+		    /* oh boy ... what is this. 
+		       movl 0, %eax
+		       cmpl %eax, %esi
+		       jnc 3f
+		    */
+		    if (eax < esi) { /* ??*/
+		      
+		      // This is the current best MA mapping.
+		      // Save the address and its MA mapping value.
+		      best = r;
+		      esi = eax;
+		    }
+		  }
+		  
+		  pci_write_config8(north,0x58, raminit_ma_reg_table[best]);
+		  print_err("enabled first bank of ram ...\n");
+		}
+	  }
+
+	print_err("vt8601 done\n");
+
 }
 
 static void sdram_set_spd_registers(const struct mem_controller *ctrl) {