versatile.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Versatile board support using the device tree
  4 *
  5 *  Copyright (C) 2010 Secret Lab Technologies Ltd.
  6 *  Copyright (C) 2009 Jeremy Kerr <jeremy.kerr@canonical.com>
  7 *  Copyright (C) 2004 ARM Limited
  8 *  Copyright (C) 2000 Deep Blue Solutions Ltd
  9 */
 10
 11#include <linux/init.h>
 12#include <linux/io.h>
 13#include <linux/of.h>
 14#include <linux/of_address.h>
 15#include <linux/of_irq.h>
 16#include <linux/of_platform.h>
 17#include <linux/slab.h>
 18#include <linux/amba/bus.h>
 19#include <linux/amba/mmci.h>
 20#include <asm/mach-types.h>
 21#include <asm/mach/arch.h>
 22#include <asm/mach/map.h>
 23
 24/* macro to get at MMIO space when running virtually */
 25#define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
 26#define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))
 27
 28/*
 29 * ------------------------------------------------------------------------
 30 *  Versatile Registers
 31 * ------------------------------------------------------------------------
 32 */
 33#define VERSATILE_SYS_PCICTL_OFFSET           0x44
 34#define VERSATILE_SYS_MCI_OFFSET              0x48
 35
 36/*
 37 * VERSATILE peripheral addresses
 38 */
 39#define VERSATILE_MMCI0_BASE           0x10005000	/* MMC interface */
 40#define VERSATILE_MMCI1_BASE           0x1000B000	/* MMC Interface */
 41#define VERSATILE_SCTL_BASE            0x101E0000	/* System controller */
 42
 43/*
 44 * System controller bit assignment
 45 */
 46#define VERSATILE_REFCLK	0
 47#define VERSATILE_TIMCLK	1
 48
 49#define VERSATILE_TIMER1_EnSel	15
 50#define VERSATILE_TIMER2_EnSel	17
 51#define VERSATILE_TIMER3_EnSel	19
 52#define VERSATILE_TIMER4_EnSel	21
 53
 54static void __iomem *versatile_sys_base;
 55
 56static unsigned int mmc_status(struct device *dev)
 57{
 58	struct amba_device *adev = container_of(dev, struct amba_device, dev);
 59	u32 mask;
 60
 61	if (adev->res.start == VERSATILE_MMCI0_BASE)
 62		mask = 1;
 63	else
 64		mask = 2;
 65
 66	return readl(versatile_sys_base + VERSATILE_SYS_MCI_OFFSET) & mask;
 67}
 68
 69static struct mmci_platform_data mmc0_plat_data = {
 70	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
 71	.status		= mmc_status,
 72};
 73
 74static struct mmci_platform_data mmc1_plat_data = {
 75	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
 76	.status		= mmc_status,
 77};
 78
 79/*
 80 * Lookup table for attaching a specific name and platform_data pointer to
 81 * devices as they get created by of_platform_populate().  Ideally this table
 82 * would not exist, but the current clock implementation depends on some devices
 83 * having a specific name.
 84 */
 85struct of_dev_auxdata versatile_auxdata_lookup[] __initdata = {
 86	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI0_BASE, "fpga:05", &mmc0_plat_data),
 87	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI1_BASE, "fpga:0b", &mmc1_plat_data),
 88	{}
 89};
 90
 91static struct map_desc versatile_io_desc[] __initdata __maybe_unused = {
 92	{
 93		.virtual	=  IO_ADDRESS(VERSATILE_SCTL_BASE),
 94		.pfn		= __phys_to_pfn(VERSATILE_SCTL_BASE),
 95		.length		= SZ_4K * 9,
 96		.type		= MT_DEVICE
 97	}
 98};
 99
100static void __init versatile_map_io(void)
101{
102	debug_ll_io_init();
103	iotable_init(versatile_io_desc, ARRAY_SIZE(versatile_io_desc));
104}
105
106static void __init versatile_init_early(void)
107{
108	u32 val;
109
110	/*
111	 * set clock frequency:
112	 *	VERSATILE_REFCLK is 32KHz
113	 *	VERSATILE_TIMCLK is 1MHz
114	 */
115	val = readl(__io_address(VERSATILE_SCTL_BASE));
116	writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
117	       (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
118	       (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
119	       (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
120	       __io_address(VERSATILE_SCTL_BASE));
121}
122
123static void __init versatile_dt_pci_init(void)
124{
125	u32 val;
126	struct device_node *np;
127	struct property *newprop;
128
129	np = of_find_compatible_node(NULL, NULL, "arm,versatile-pci");
130	if (!np)
131		return;
132
133	/* Check if PCI backplane is detected */
134	val = readl(versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
135	if (val & 1) {
136		/*
137		 * Enable PCI accesses. Note that the documentation is
138		 * inconsistent whether or not this is needed, but the old
139		 * driver had it so we will keep it.
140		 */
141		writel(1, versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
142		goto out_put_node;
143	}
144
145	newprop = kzalloc(sizeof(*newprop), GFP_KERNEL);
146	if (!newprop)
147		goto out_put_node;
148
149	newprop->name = kstrdup("status", GFP_KERNEL);
150	newprop->value = kstrdup("disabled", GFP_KERNEL);
151	newprop->length = sizeof("disabled");
152	of_update_property(np, newprop);
153
154	pr_info("Not plugged into PCI backplane!\n");
155
156out_put_node:
157	of_node_put(np);
158}
159
160static void __init versatile_dt_init(void)
161{
162	struct device_node *np;
163
164	np = of_find_compatible_node(NULL, NULL, "arm,core-module-versatile");
165	if (np)
166		versatile_sys_base = of_iomap(np, 0);
167	WARN_ON(!versatile_sys_base);
168
169	versatile_dt_pci_init();
170
171	of_platform_default_populate(NULL, versatile_auxdata_lookup, NULL);
172}
173
174static const char *const versatile_dt_match[] __initconst = {
175	"arm,versatile-ab",
176	"arm,versatile-pb",
177	NULL,
178};
179
180DT_MACHINE_START(VERSATILE_PB, "ARM-Versatile (Device Tree Support)")
181	.map_io		= versatile_map_io,
182	.init_early	= versatile_init_early,
183	.init_machine	= versatile_dt_init,
184	.dt_compat	= versatile_dt_match,
185MACHINE_END