arm: mvebu: theadorable: Add PEX-switch detection and reset code

Sometimes the PCIe link for the PEX-switch will not come-up. In this case,
the board is not in a usable state. This patch makes sure that in this
case a soft-reset is issued. If this soft-reset does not result in the
PEX-switch being detected after some soft-reset cycles, an I2C message
is sent to the uC to issue a complete power-cycle of the board.

Signed-off-by: Stefan Roese <sr@denx.de>

diff --git a/board/theadorable/theadorable.c b/board/theadorable/theadorable.c
index 0756f18..b8b0148 100644 (file)
--- a/board/theadorable/theadorable.c
+++ b/board/theadorable/theadorable.c
@@ -5,10 +5,13 @@
  */
 
 #include <common.h>
+#include <i2c.h>
+#include <pci.h>
 #include <asm/gpio.h>
 #include <asm/io.h>
 #include <asm/arch/cpu.h>
 #include <asm/arch/soc.h>
+#include <linux/crc8.h>
 #include <linux/mbus.h>
 #ifdef CONFIG_NET
 #include <netdev.h>
@@ -35,6 +38,12 @@ DECLARE_GLOBAL_DATA_PTR;
 #define GPIO_USB0_PWR_ON               18
 #define GPIO_USB1_PWR_ON               19
 
+#define PEX_SWITCH_NOT_FOUNT_LIMIT     3
+
+#define STM_I2C_BUS    1
+#define STM_I2C_ADDR   0x27
+#define REBOOT_DELAY   1000            /* reboot-delay in ms */
+
 /* DDR3 static configuration */
 static MV_DRAM_MC_INIT ddr3_theadorable[MV_MAX_DDR3_STATIC_SIZE] = {
        {0x00001400, 0x7301ca28},       /* DDR SDRAM Configuration Register */
@@ -214,3 +223,63 @@ int board_video_init(void)
 
        return mvebu_lcd_register_init(&lcd_info);
 }
+
+#ifdef CONFIG_BOARD_LATE_INIT
+int board_late_init(void)
+{
+       pci_dev_t bdf;
+       ulong bootcount;
+
+       /*
+        * Check if the PEX switch is detected (somtimes its not available
+        * on the PCIe bus). In this case, try to recover by issuing a
+        * soft-reset or even a power-cycle, depending on the bootcounter
+        * value.
+        */
+       bdf = pci_find_device(PCI_VENDOR_ID_PLX, 0x8619, 0);
+       if (bdf == -1) {
+               u8 i2c_buf[8];
+               int ret;
+
+               /* PEX switch not found! */
+               bootcount = bootcount_load();
+               printf("Failed to find PLX PEX-switch (bootcount=%ld)\n",
+                      bootcount);
+               if (bootcount > PEX_SWITCH_NOT_FOUNT_LIMIT) {
+                       printf("Issuing power-switch via uC!\n");
+
+                       printf("Issuing power-switch via uC!\n");
+                       i2c_set_bus_num(STM_I2C_BUS);
+                       i2c_buf[0] = STM_I2C_ADDR << 1;
+                       i2c_buf[1] = 0xc5;      /* cmd */
+                       i2c_buf[2] = 0x01;      /* enable */
+                       /* Delay before reboot */
+                       i2c_buf[3] = REBOOT_DELAY & 0x00ff;
+                       i2c_buf[4] = (REBOOT_DELAY & 0xff00) >> 8;
+                       /* Delay before shutdown */
+                       i2c_buf[5] = 0x00;
+                       i2c_buf[6] = 0x00;
+                       i2c_buf[7] = crc8(0x72, &i2c_buf[0], 7);
+
+                       ret = i2c_write(STM_I2C_ADDR, 0, 0, &i2c_buf[1], 7);
+                       if (ret) {
+                               printf("I2C write error (ret=%d)\n", ret);
+                               printf("Issuing soft-reset...\n");
+                               /* default handling: SOFT reset */
+                               do_reset(NULL, 0, 0, NULL);
+                       }
+
+                       /* Wait for power-cycle to occur... */
+                       printf("Waiting for power-cycle via uC...\n");
+                       while (1)
+                               ;
+               } else {
+                       printf("Issuing soft-reset...\n");
+                       /* default handling: SOFT reset */
+                       do_reset(NULL, 0, 0, NULL);
+               }
+       }
+
+       return 0;
+}
+#endif

diff --git a/include/configs/theadorable.h b/include/configs/theadorable.h
index 05a248e..5864f27 100644 (file)
--- a/include/configs/theadorable.h
+++ b/include/configs/theadorable.h
@@ -104,6 +104,7 @@
 #define CONFIG_PCI
 #define CONFIG_PCI_MVEBU
 #define CONFIG_PCI_PNP
+#define CONFIG_BOARD_LATE_INIT         /* for PEX switch test */
 #endif
 #endif