[U-Boot] [PATCH v4 05/12] SPEAr : nand driver support for SPEAr SoCs

[Tom <Tom.Rix@windriver.com>]

SPEAr SoCs contain an FSMC controller which can be used to interface
with a range of memories eg. NAND, SRAM, NOR.
Currently, this driver supports interfacing FSMC with NAND memories

Signed-off-by: Vipin <vipin.kumar@st.com>
---
  drivers/mtd/nand/Makefile             |    1 +
  drivers/mtd/nand/spr_nand.c           |  123 +++++++++++++++++++++++++++++++++
  include/asm-arm/arch-spear/spr_nand.h |   57 +++++++++++++++
  3 files changed, 181 insertions(+), 0 deletions(-)
  create mode 100755 drivers/mtd/nand/spr_nand.c
  create mode 100644 include/asm-arm/arch-spear/spr_nand.h

<snip>
+}
+
+static int spear_read_hwecc(struct mtd_info *mtd,
+			    const u_char *data, u_char ecc[3])
+{
+	u_int ecc_tmp;
+
+	/* read the h/w ECC */
+	ecc_tmp = readl(&fsmc_regs_p->genmemctrl_ecc);
+
+	ecc[0] = (u_char) (ecc_tmp & 0xFF);
+	ecc[1] = (u_char) ((ecc_tmp & 0xFF00) >> 8);
+	ecc[2] = (u_char) ((ecc_tmp & 0xFF0000) >> 16);
+
+	return 0;

Always returning 0.
return can be switched to void

+}
+
+void spear_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+	writel(readl(&fsmc_regs_p->genmemctrl_pc) & ~0x80,
+	       &fsmc_regs_p->genmemctrl_pc);
+	writel(readl(&fsmc_regs_p->genmemctrl_pc) & ~FSMC_ECCEN,
+	       &fsmc_regs_p->genmemctrl_pc);
+	writel(readl(&fsmc_regs_p->genmemctrl_pc) | FSMC_ECCEN,
+	       &fsmc_regs_p->genmemctrl_pc);
+}
+
+int spear_nand_init(struct nand_chip *nand)
+{
+	writel(FSMC_DEVWID_8 | FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON,
+	       &fsmc_regs_p->genmemctrl_pc);
+	writel(readl(&fsmc_regs_p->genmemctrl_pc) | FSMC_TCLR_1 | FSMC_TAR_1,
+	       &fsmc_regs_p->genmemctrl_pc);
+	writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
+	       &fsmc_regs_p->genmemctrl_comm);
+	writel(FSMC_THIZ_1 | FSMC_THOLD_4 | FSMC_TWAIT_6 | FSMC_TSET_0,
+	       &fsmc_regs_p->genmemctrl_attrib);
+
+	nand->options = 0;
+	nand->ecc.mode = NAND_ECC_HW;
+	nand->ecc.layout = &spear_nand_ecclayout;
+	nand->ecc.size = 512;
+	nand->ecc.bytes = 3;
+	nand->ecc.calculate = spear_read_hwecc;
+	nand->ecc.hwctl = spear_enable_hwecc;
+	nand->ecc.correct = nand_correct_data;
+	nand->cmd_ctrl = spear_nand_hwcontrol;
+	return 0;
Same here for returning void.
These are just minor things.
Change is optional.
+}

Tom