Do not init SATA when disabled on 8536DS.

SGMII and SATA share the serdes on MPC8536 CPU, When SATA disabled and the
driver still try to access the SATA registers, the cpu will hangup.
This patch try to fix this by reading the serdes status before the SATA
initialize.

Signed-off-by: Jason Jin <Jason.jin@freescale.com>
Acked-by: Andy Fleming <afleming@freescale.com>

board/freescale/mpc8536ds/mpc8536ds.c

@@ -608,6 +608,18 @@ get_board_ddr_clk(ulong dummy)
 }
 #endif
 
+int is_sata_supported()
+{
+	volatile ccsr_gur_t *gur = (void *)(CFG_MPC85xx_GUTS_ADDR);
+	uint devdisr = gur->devdisr;
+	uint sdrs2_io_sel =
+		(gur->pordevsr & MPC85xx_PORDEVSR_SRDS2_IO_SEL) >> 27;
+	if (sdrs2_io_sel & 0x04)
+		return 0;
+
+	return 1;
+}
+
 #if defined(CONFIG_OF_BOARD_SETUP)
 void
 ft_board_setup(void *blob, bd_t *bd)

lib_ppc/board.c

@@ -635,6 +635,16 @@ void board_init_f (ulong bootflag)
 	/* NOTREACHED - relocate_code() does not return */
 }
 
+int __is_sata_supported()
+{
+	/* For some boards, when sata disabled by the switch, and the
+	 * driver still access the sata registers, the cpu will hangup.
+	 * please define platform specific is_sata_supported() if your
+	 * board have such issue.*/
+	return 1;
+}
+int is_sata_supported() __attribute__((weak, alias("__is_sata_supported")));
+
 /************************************************************************
  *
  * This is the next part if the initialization sequence: we are now
@@ -1105,8 +1115,10 @@ void board_init_r (gd_t *id, ulong dest_addr)
 #endif
 
 #if defined(CONFIG_CMD_SATA)
-	puts ("SATA:  ");
-	sata_initialize ();
+	if (is_sata_supported()) {
+		puts("SATA:  ");
+		sata_initialize();
+	}
 #endif
 
 #ifdef CONFIG_LAST_STAGE_INIT