[SMBus] Add support for ALi M1563 Southbridge (#272)

system/smbus.c

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2004-2022 Samuel Demeulemeester
+// Copyright (C) 2004-2023 Sam Demeulemeester
 
 #include "display.h"
 
@@ -53,6 +53,7 @@ static bool ich5_get_smb(void);
 static uint8_t ich5_process(void);
 static uint8_t ich5_read_spd_byte(uint8_t adr, uint16_t cmd);
 static uint8_t nf_read_spd_byte(uint8_t smbus_adr, uint8_t spd_adr);
+static uint8_t ali_read_spd_byte(uint8_t smbus_adr, uint8_t spd_adr);
 
 static inline uint8_t bcd_to_ui8(uint8_t bcd)
 {
@@ -1282,8 +1283,9 @@ static bool find_smb_controller(uint16_t vid, uint16_t did)
         case PCI_VID_ALI:
             switch(did)
             {
-                // case 0x1563: // ali1563 (M1563) SMBus controller, nearly compatible with PIIX4 according to Linux i2c-ali1563 driver.
+                // case 0x7101: // ALi M1533/1535/1543
-                // case 0x7101: // ali1535 (M1535) or ali15x3 (M1533/M1543) SMBus controllers
+                case 0x1563: // ALi M1563
+                    return piix4_get_smb(PIIX4_SMB_BASE_ADR_ALI1563);
                 default:
                     return false;
             }
@@ -1444,6 +1446,8 @@ static bool nv_mcp_get_smb(void)
 static uint8_t get_spd(uint8_t slot_idx, uint16_t spd_adr)
 {
     switch ((smbus_id >> 16) & 0xFFFF) {
+      case PCI_VID_ALI:
+        return ali_read_spd_byte(slot_idx, (uint8_t)spd_adr);
       case PCI_VID_NVIDIA:
         return nf_read_spd_byte(slot_idx, (uint8_t)spd_adr);
       default:
@@ -1586,3 +1590,38 @@ static uint8_t nf_read_spd_byte(uint8_t smbus_adr, uint8_t spd_adr)
 
     return __inb(NVSMBDAT(0));
 }
+
+static uint8_t ali_read_spd_byte(uint8_t smbus_adr, uint8_t spd_adr)
+{
+    int i;
+
+    smbus_adr += 0x50;
+
+    // Reset Status Register
+     __outb(0xFF, SMBHSTSTS);
+
+    // Set Slave ADR
+    __outb((smbus_adr << 1 | I2C_READ), SMBHSTADD);
+
+    __outb((__inb(SMBHSTCNT) & ~ALI_SMBHSTCNT_SIZEMASK) | (ALI_SMBHSTCNT_BYTE_DATA << 3), SMBHSTCNT);
+
+    // Set Command (SPD Byte to Read)
+    __outb(spd_adr, SMBHSTCMD);
+
+    // Start transaction
+    __outb(__inb(SMBHSTCNT) | SMBHSTCNT_START, SMBHSTCNT);
+
+    // Wait until transaction complete
+    for (i = 500; i > 0; i--) {
+        usleep(50);
+        if (!(__inb(SMBHSTSTS) & SMBHSTSTS_HOST_BUSY)) {
+            break;
+        }
+    }
+    // If timeout or Error Status, exit
+    if (i == 0 || __inb(SMBHSTSTS) & ALI_SMBHSTSTS_BAD) {
+        return 0xFF;
+    }
+
+    return __inb(SMBHSTDAT0);
+}

system/smbus.h

@@ -7,7 +7,7 @@
  *
  * Provides functions for reading SPD via SMBUS
  *
- * Copyright (C) 2004-2022 Samuel Demeulemeester.
+ * Copyright (C) 2004-2023 Sam Demeulemeester.
  */
 
 #define I2C_WRITE   0
@@ -74,6 +74,17 @@
 #define NVSMBSTS_RES        0x20
 #define NVSMBSTS_STATUS     0x1f
 
+/* ALi-Specific constants */
+#define ALI_SMBHSTCNT_SIZEMASK  0x03
+#define ALI_SMBHSTSTS_BAD       0x1C
+
+#define ALI_SMBHSTCNT_QUICK     0x00
+#define ALI_SMBHSTCNT_BYTE      0x01
+#define ALI_SMBHSTCNT_BYTE_DATA 0x02
+#define ALI_SMBHSTCNT_WORD_DATA 0x03
+#define ALI_SMBHSTCNT_KILL      0x04
+#define ALI_SMBHSTCNT_BLOCK     0x05
+
 /** Rounding factors for timing computation
  *
  *  These factors are used as a configurable CEIL() function
@@ -87,6 +98,7 @@
 
 #define PIIX4_SMB_BASE_ADR_DEFAULT  0x90
 #define PIIX4_SMB_BASE_ADR_VIAPRO   0xD0
+#define PIIX4_SMB_BASE_ADR_ALI1563  0x80
 
 struct pci_smbus_controller {
     unsigned vendor;