esdhc: Workaround for card can't be detected on T4240QDS

Card detection pin is ineffective on T4240QDS Rev1.0.
There are two cards can be connected to board.
1. eMMC card is built-in board, can not be removed. so
   For eMMC card it is always there.
2. Card detecting pin is functional for SDHC card in Rev2.0.

This workaround force sdhc driver scan and initialize the card
regardless of whether the card is inserted or not in case Rev1.0.

Signed-off-by: Haijun Zhang <Haijun.Zhang@freescale.com>
Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Reviewed-by: York Sun <yorksun@freescale.com>

drivers/mmc/fsl_esdhc.c

@@ -500,6 +500,10 @@ static int esdhc_getcd(struct mmc *mmc)
 	struct fsl_esdhc *regs = (struct fsl_esdhc *)cfg->esdhc_base;
 	int timeout = 1000;
 
+#ifdef CONFIG_ESDHC_DETECT_QUIRK
+	if (CONFIG_ESDHC_DETECT_QUIRK)
+		return 1;
+#endif
 	while (!(esdhc_read32(&regs->prsstat) & PRSSTAT_CINS) && --timeout)
 		udelay(1000);
 

include/configs/T4240QDS.h

@@ -165,6 +165,8 @@ unsigned long get_board_ddr_clk(void);
 #define QIXIS_RCFG_CTL_RECONFIG_IDLE	0x20
 #define QIXIS_RCFG_CTL_RECONFIG_START	0x21
 #define QIXIS_RCFG_CTL_WATCHDOG_ENBLE	0x08
+#define QIXIS_BRDCFG5			0x55
+#define QIXIS_MUX_SDHC			2
 #define QIXIS_BASE_PHYS		(0xf00000000ull | QIXIS_BASE)
 
 #define CONFIG_SYS_CSPR3_EXT	(0xf)
@@ -466,6 +468,9 @@ unsigned long get_board_ddr_clk(void);
 #define CONFIG_CMD_FAT
 #define CONFIG_DOS_PARTITION
 #define CONFIG_SYS_FSL_MMC_HAS_CAPBLT_VS33
+#define CONFIG_ESDHC_DETECT_QUIRK \
+	(!(readb(QIXIS_BASE + QIXIS_BRDCFG5) & QIXIS_MUX_SDHC) || \
+	IS_SVR_REV(get_svr(), 1, 0))
 #endif
 
 #define CONFIG_BOOTDELAY	10	/* -1 disables auto-boot */