// SPDX-License-Identifier: GPL-2.0-or-later/* * Versatile OF physmap driver add-on * * Copyright (c) 2016, Linaro Limited * Author: Linus Walleij <linus.walleij@linaro.org> */#include <linux/export.h>#include <linux/io.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/mtd/map.h>#include <linux/mfd/syscon.h>#include <linux/platform_device.h>#include <linux/regmap.h>#include <linux/bitops.h>#include "physmap-versatile.h" static struct regmap *syscon_regmap; enum versatile_flashprot {	INTEGRATOR_AP_FLASHPROT,	INTEGRATOR_CP_FLASHPROT,	VERSATILE_FLASHPROT,	REALVIEW_FLASHPROT,}; static const struct of_device_id syscon_match[] = {	{		.compatible = "arm,integrator-ap-syscon",		.data = (void *)INTEGRATOR_AP_FLASHPROT,	},	{		.compatible = "arm,integrator-cp-syscon",		.data = (void *)INTEGRATOR_CP_FLASHPROT,	},	{		.compatible = "arm,core-module-versatile",		.data = (void *)VERSATILE_FLASHPROT,	},	{		.compatible = "arm,realview-eb-syscon",		.data = (void *)REALVIEW_FLASHPROT,	},	{		.compatible = "arm,realview-pb1176-syscon",		.data = (void *)REALVIEW_FLASHPROT,	},	{		.compatible = "arm,realview-pb11mp-syscon",		.data = (void *)REALVIEW_FLASHPROT,	},	{		.compatible = "arm,realview-pba8-syscon",		.data = (void *)REALVIEW_FLASHPROT,	},	{		.compatible = "arm,realview-pbx-syscon",		.data = (void *)REALVIEW_FLASHPROT,	},	{},}; /* * Flash protection handling for the Integrator/AP */#define INTEGRATOR_SC_CTRLS_OFFSET	0x08#define INTEGRATOR_SC_CTRLC_OFFSET	0x0C#define INTEGRATOR_SC_CTRL_FLVPPEN	BIT(1)#define INTEGRATOR_SC_CTRL_FLWP		BIT(2) #define INTEGRATOR_EBI_CSR1_OFFSET	0x04/* The manual says bit 2, the code says bit 3, trust the code */#define INTEGRATOR_EBI_WRITE_ENABLE	BIT(3)#define INTEGRATOR_EBI_LOCK_OFFSET	0x20#define INTEGRATOR_EBI_LOCK_VAL		0xA05F static const struct of_device_id ebi_match[] = {	{ .compatible = "arm,external-bus-interface"},	{ },}; static int ap_flash_init(struct platform_device *pdev){	struct device_node *ebi;	void __iomem *ebi_base;	u32 val;	int ret; 	/* Look up the EBI */	ebi = of_find_matching_node(NULL, ebi_match);	if (!ebi) {		return -ENODEV;	}	ebi_base = of_iomap(ebi, 0);	of_node_put(ebi);	if (!ebi_base)		return -ENODEV; 	/* Clear VPP and write protection bits */	ret = regmap_write(syscon_regmap,		INTEGRATOR_SC_CTRLC_OFFSET,		INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP);	if (ret)		dev_err(&pdev->dev, "error clearing Integrator VPP/WP\n"); 	/* Unlock the EBI */	writel(INTEGRATOR_EBI_LOCK_VAL, ebi_base + INTEGRATOR_EBI_LOCK_OFFSET); 	/* Enable write cycles on the EBI, CSR1 (flash) */	val = readl(ebi_base + INTEGRATOR_EBI_CSR1_OFFSET);	val |= INTEGRATOR_EBI_WRITE_ENABLE;	writel(val, ebi_base + INTEGRATOR_EBI_CSR1_OFFSET); 	/* Lock the EBI again */	writel(0, ebi_base + INTEGRATOR_EBI_LOCK_OFFSET);	iounmap(ebi_base); 	return 0;} static void ap_flash_set_vpp(struct map_info *map, int on){	int ret; 	if (on) {		ret = regmap_write(syscon_regmap,			INTEGRATOR_SC_CTRLS_OFFSET,			INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP);		if (ret)			pr_err("error enabling AP VPP\n");	} else {		ret = regmap_write(syscon_regmap,			INTEGRATOR_SC_CTRLC_OFFSET,			INTEGRATOR_SC_CTRL_FLVPPEN | INTEGRATOR_SC_CTRL_FLWP);		if (ret)			pr_err("error disabling AP VPP\n");	}} /* * Flash protection handling for the Integrator/CP */ #define INTCP_FLASHPROG_OFFSET		0x04#define CINTEGRATOR_FLVPPEN		BIT(0)#define CINTEGRATOR_FLWREN		BIT(1)#define CINTEGRATOR_FLMASK		BIT(0)|BIT(1) static void cp_flash_set_vpp(struct map_info *map, int on){	int ret; 	if (on) {		ret = regmap_update_bits(syscon_regmap,				INTCP_FLASHPROG_OFFSET,				CINTEGRATOR_FLMASK,				CINTEGRATOR_FLVPPEN | CINTEGRATOR_FLWREN);		if (ret)			pr_err("error setting CP VPP\n");	} else {		ret = regmap_update_bits(syscon_regmap,				INTCP_FLASHPROG_OFFSET,				CINTEGRATOR_FLMASK,				0);		if (ret)			pr_err("error setting CP VPP\n");	}} /* * Flash protection handling for the Versatiles and RealViews */ #define VERSATILE_SYS_FLASH_OFFSET            0x4C static void versatile_flash_set_vpp(struct map_info *map, int on){	int ret; 	ret = regmap_update_bits(syscon_regmap, VERSATILE_SYS_FLASH_OFFSET,				 0x01, !!on);	if (ret)		pr_err("error setting Versatile VPP\n");} int of_flash_probe_versatile(struct platform_device *pdev,			     struct device_node *np,			     struct map_info *map){	struct device_node *sysnp;	const struct of_device_id *devid;	struct regmap *rmap;	static enum versatile_flashprot versatile_flashprot;	int ret; 	/* Not all flash chips use this protection line */	if (!of_device_is_compatible(np, "arm,versatile-flash"))		return 0; 	/* For first chip probed, look up the syscon regmap */	if (!syscon_regmap) {		sysnp = of_find_matching_node_and_match(NULL,							syscon_match,							&devid);		if (!sysnp)			return -ENODEV; 		versatile_flashprot = (uintptr_t)devid->data;		rmap = syscon_node_to_regmap(sysnp);		of_node_put(sysnp);		if (IS_ERR(rmap))			return PTR_ERR(rmap); 		syscon_regmap = rmap;	} 	switch (versatile_flashprot) {	case INTEGRATOR_AP_FLASHPROT:		ret = ap_flash_init(pdev);		if (ret)			return ret;		map->set_vpp = ap_flash_set_vpp;		dev_info(&pdev->dev, "Integrator/AP flash protection\n");		break;	case INTEGRATOR_CP_FLASHPROT:		map->set_vpp = cp_flash_set_vpp;		dev_info(&pdev->dev, "Integrator/CP flash protection\n");		break;	case VERSATILE_FLASHPROT:	case REALVIEW_FLASHPROT:		map->set_vpp = versatile_flash_set_vpp;		dev_info(&pdev->dev, "versatile/realview flash protection\n");		break;	default:		dev_info(&pdev->dev, "device marked as Versatile flash "			 "but no system controller was found\n");		break;	} 	return 0;}