board: sl28: add SATA support

Enable SATA support. Although not supported by the usual SATA pins on
the SMARC baseboard connector, SATA mode is supported on a PCIe lane.
This way one can use a mSATA card in a Mini PCI slot.

We need to invert the received data because in this mode the polarity of
the SerDes lane is swapped. Provide a fixup in board_early_init_f() for
the SPL. board_early_init_f() is then not common between SPL and u-boot
proper anymore, thus common.c is removed, as it just contained said
function.

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>

arch/arm/dts/fsl-ls1028a-kontron-sl28.dts

@@ -172,6 +172,10 @@
 	};
 };
 
+&sata {
+	status = "okay";
+};
+
 &serial0 {
 	status = "okay";
 };

board/kontron/sl28/Makefile

@@ -4,7 +4,7 @@ ifndef CONFIG_SPL_BUILD
 obj-y += sl28.o cmds.o
 endif
 
-obj-y += common.o ddr.o
+obj-y += ddr.o
 
 ifdef CONFIG_SPL_BUILD
 obj-y += spl.o

board/kontron/sl28/common.c

@@ -1,10 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-
-#include <common.h>
-#include <asm/arch-fsl-layerscape/soc.h>
-
-int board_early_init_f(void)
-{
-	fsl_lsch3_early_init_f();
-	return 0;
-}

board/kontron/sl28/sl28.c

@@ -19,6 +19,12 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+int board_early_init_f(void)
+{
+	fsl_lsch3_early_init_f();
+	return 0;
+}
+
 int board_init(void)
 {
 	if (CONFIG_IS_ENABLED(FSL_CAAM))

board/kontron/sl28/spl.c

@@ -3,10 +3,36 @@
 #include <common.h>
 #include <asm/io.h>
 #include <asm/spl.h>
+#include <asm/arch-fsl-layerscape/fsl_serdes.h>
+#include <asm/arch-fsl-layerscape/soc.h>
 
 #define DCFG_RCWSR25 0x160
 #define GPINFO_HW_VARIANT_MASK 0xff
 
+#define SERDES_LNDGCR0		0x1ea08c0
+#define   LNDGCR0_PROTS_MASK	GENMASK(11, 7)
+#define   LNDGCR0_PROTS_SATA	(0x2 << 7)
+#define SERDES_LNDGCR1		0x1ea08c4
+#define   LNDGCR1_RDAT_INV	BIT(31)
+
+/*
+ * On this board the SMARC PCIe lane D might be switched to SATA mode. This
+ * makes sense if this lane is connected to a Mini PCI slot and a mSATA card
+ * is plugged in. In this case, the RX pair is swapped and we need to invert
+ * the received data.
+ */
+static void fixup_sata_rx_polarity(void)
+{
+	u32 prot = in_le32(SERDES_LNDGCR0) & LNDGCR0_PROTS_MASK;
+	u32 tmp;
+
+	if (prot == LNDGCR0_PROTS_SATA) {
+		tmp = in_le32(SERDES_LNDGCR1);
+		tmp |= LNDGCR1_RDAT_INV;
+		out_le32(SERDES_LNDGCR1, tmp);
+	}
+}
+
 int sl28_variant(void)
 {
 	return in_le32(DCFG_BASE + DCFG_RCWSR25) & GPINFO_HW_VARIANT_MASK;
@@ -34,3 +60,11 @@ void board_boot_order(u32 *spl_boot_list)
 {
 	spl_boot_list[0] = BOOT_DEVICE_SPI;
 }
+
+int board_early_init_f(void)
+{
+	fixup_sata_rx_polarity();
+	fsl_lsch3_early_init_f();
+
+	return 0;
+}

configs/kontron_sl28_defconfig

@@ -62,6 +62,7 @@ CONFIG_DM=y
 CONFIG_SPL_DM=y
 CONFIG_SPL_DM_SEQ_ALIAS=y
 CONFIG_SCSI_AHCI=y
+CONFIG_SATA_CEVA=y
 CONFIG_FSL_CAAM=y
 CONFIG_SYS_FSL_DDR3=y
 CONFIG_DM_I2C=y

include/configs/kontron_sl28.h

@@ -93,6 +93,7 @@
 	func(MMC, mmc, 1) \
 	func(NVME, nvme, 0) \
 	func(USB, usb, 0) \
+	func(SCSI, scsi, 0) \
 	func(DHCP, dhcp, 0) \
 	func(PXE, pxe, 0)
 #include <config_distro_bootcmd.h>