mtd: rawnand: omap_elm: u-boot driver model support

Support u-boot driver model. We still retain
support legacy way of doing things if ELM_BASE
is defined in <asm/arch/hardware.h>

We could completely get rid of that if all
platforms defining ELM_BASE get rid of that definition
and enable CONFIG_SYS_NAND_SELF_INIT and are verified
to work.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Link: https://lore.kernel.org/all/20221220102203.52398-9-rogerq@kernel.org
Link: https://lore.kernel.org/all/CABGWkvrvKiVA_yaDnHJcHEKwc+pEuLdz=i6HQEY0oJQvohCUsw@mail.gmail.com

3 files changed, 133 insertions, 2 deletions

diff --git a/drivers/mtd/nand/raw/omap_elm.c b/drivers/mtd/nand/raw/omap_elm.c
index 35c6dd1f1b..56a2c39e4f 100644
--- a/drivers/mtd/nand/raw/omap_elm.c
+++ b/drivers/mtd/nand/raw/omap_elm.c
@@ -15,9 +15,14 @@
 #include <common.h>
 #include <asm/io.h>
 #include <linux/errno.h>
-#include <linux/mtd/omap_elm.h>
 #include <asm/arch/hardware.h>
 
+#include <dm.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+
+#include "omap_elm.h"
+
 #define DRIVER_NAME		"omap-elm"
 #define ELM_DEFAULT_POLY (0)
 
@@ -180,6 +185,7 @@ void elm_reset(void)
 		;
 }
 
+#ifdef ELM_BASE
 /**
  * elm_init - Initialize ELM module
  *
@@ -191,3 +197,33 @@ void elm_init(void)
 	elm_cfg = (struct elm *)ELM_BASE;
 	elm_reset();
 }
+#endif
+
+#if CONFIG_IS_ENABLED(SYS_NAND_SELF_INIT)
+
+static int elm_probe(struct udevice *dev)
+{
+#ifndef ELM_BASE
+	struct resource res;
+
+	dev_read_resource(dev, 0, &res);
+	elm_cfg = devm_ioremap(dev, res.start, resource_size(&res));
+	elm_reset();
+#endif
+
+	return 0;
+}
+
+static const struct udevice_id elm_ids[] = {
+	{ .compatible = "ti,am3352-elm" },
+	{ .compatible = "ti,am64-elm" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpmc_elm) = {
+	.name           = DRIVER_NAME,
+	.id             = UCLASS_MTD,
+	.of_match       = elm_ids,
+	.probe          = elm_probe,
+};
+#endif /* CONFIG_SYS_NAND_SELF_INIT */
diff --git a/drivers/mtd/nand/raw/omap_elm.h b/drivers/mtd/nand/raw/omap_elm.h
new file mode 100644
index 0000000000..a7f7bacb15
--- /dev/null
+++ b/drivers/mtd/nand/raw/omap_elm.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2010-2011 Texas Instruments, <www.ti.com>
+ * Mansoor Ahamed <mansoor.ahamed@ti.com>
+ *
+ * Derived from work done by Rohit Choraria <rohitkc@ti.com> for omap3
+ */
+#ifndef __ASM_ARCH_ELM_H
+#define __ASM_ARCH_ELM_H
+/*
+ * ELM Module Registers
+ */
+
+/* ELM registers bit fields */
+#define ELM_SYSCONFIG_SOFTRESET_MASK			(0x2)
+#define ELM_SYSCONFIG_SOFTRESET			(0x2)
+#define ELM_SYSSTATUS_RESETDONE_MASK			(0x1)
+#define ELM_SYSSTATUS_RESETDONE			(0x1)
+#define ELM_LOCATION_CONFIG_ECC_BCH_LEVEL_MASK		(0x3)
+#define ELM_LOCATION_CONFIG_ECC_SIZE_MASK		(0x7FF0000)
+#define ELM_LOCATION_CONFIG_ECC_SIZE_POS		(16)
+#define ELM_SYNDROME_FRAGMENT_6_SYNDROME_VALID		(0x00010000)
+#define ELM_LOCATION_STATUS_ECC_CORRECTABLE_MASK	(0x100)
+#define ELM_LOCATION_STATUS_ECC_NB_ERRORS_MASK		(0x1F)
+
+#define ELM_MAX_CHANNELS				8
+#define ELM_MAX_ERROR_COUNT				16
+
+#ifndef __ASSEMBLY__
+
+enum bch_level {
+	BCH_4_BIT = 0,
+	BCH_8_BIT,
+	BCH_16_BIT
+};
+
+
+/* BCH syndrome registers */
+struct syndrome {
+	u32 syndrome_fragment_x[7];	/* 0x400, 0x404.... 0x418 */
+	u8 res1[36];			/* 0x41c */
+};
+
+/* BCH error status & location register */
+struct location {
+	u32 location_status;		/* 0x800 */
+	u8 res1[124];			/* 0x804 */
+	u32 error_location_x[ELM_MAX_ERROR_COUNT]; /* 0x880, 0x980, .. */
+	u8 res2[64];			/* 0x8c0 */
+};
+
+/* BCH ELM register map - do not try to allocate memmory for this structure.
+ * We have used plenty of reserved variables to fill the slots in the ELM
+ * register memory map.
+ * Directly initialize the struct pointer to ELM base address.
+ */
+struct elm {
+	u32 rev;				/* 0x000 */
+	u8 res1[12];				/* 0x004 */
+	u32 sysconfig;				/* 0x010 */
+	u32 sysstatus;				/* 0x014 */
+	u32 irqstatus;				/* 0x018 */
+	u32 irqenable;				/* 0x01c */
+	u32 location_config;			/* 0x020 */
+	u8 res2[92];				/* 0x024 */
+	u32 page_ctrl;				/* 0x080 */
+	u8 res3[892];				/* 0x084 */
+	struct  syndrome syndrome_fragments[ELM_MAX_CHANNELS]; /* 0x400,0x420 */
+	u8 res4[512];				/* 0x600 */
+	struct location  error_location[ELM_MAX_CHANNELS]; /* 0x800,0x900 ... */
+};
+
+int elm_check_error(u8 *syndrome, enum bch_level bch_type, u32 *error_count,
+		u32 *error_locations);
+int elm_config(enum bch_level level);
+void elm_reset(void);
+#ifdef ELM_BASE
+void elm_init(void);
+#else
+static inline void elm_init(void)
+{
+}
+#endif
+#endif /* __ASSEMBLY__ */
+#endif /* __ASM_ARCH_ELM_H */
diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c
index 4d5f2455df..1a5ed0de31 100644
--- a/drivers/mtd/nand/raw/omap_gpmc.c
+++ b/drivers/mtd/nand/raw/omap_gpmc.c
@@ -20,7 +20,8 @@
 #include <linux/bch.h>
 #include <linux/compiler.h>
 #include <nand.h>
-#include <linux/mtd/omap_elm.h>
+
+#include "omap_elm.h"
 
 #ifndef GPMC_MAX_CS
 #define GPMC_MAX_CS	4
@@ -1249,6 +1250,15 @@ void board_nand_init(void)
 	struct udevice *dev;
 	int ret;
 
+#ifdef CONFIG_NAND_OMAP_ELM
+	ret = uclass_get_device_by_driver(UCLASS_MTD,
+					  DM_DRIVER_GET(gpmc_elm), &dev);
+	if (ret && ret != -ENODEV) {
+		pr_err("%s: Failed to get ELM device: %d\n", __func__, ret);
+		return;
+	}
+#endif
+
 	ret = uclass_get_device_by_driver(UCLASS_MTD,
 					  DM_DRIVER_GET(gpmc_nand), &dev);
 	if (ret && ret != -ENODEV)