1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PowerPC 476FPE board specific routines
4 *
5 * Copyright © 2013 Tony Breeds IBM Corporation
6 * Copyright © 2013 Alistair Popple IBM Corporation
7 *
8 * Based on earlier code:
9 *    Matt Porter <mporter@kernel.crashing.org>
10 *    Copyright 2002-2005 MontaVista Software Inc.
11 *
12 *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
13 *    Copyright (c) 2003-2005 Zultys Technologies
14 *
15 *    Rewritten and ported to the merged powerpc tree:
16 *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
17 *    Copyright © 2011 David Kliekamp IBM Corporation
18 */
19
20#include <linux/init.h>
21#include <linux/of.h>
22#include <linux/of_platform.h>
23#include <linux/rtc.h>
24
25#include <asm/machdep.h>
26#include <asm/prom.h>
27#include <asm/udbg.h>
28#include <asm/time.h>
29#include <asm/uic.h>
30#include <asm/ppc4xx.h>
31#include <asm/mpic.h>
32#include <asm/mmu.h>
33#include <asm/swiotlb.h>
34
35#include <linux/pci.h>
36#include <linux/i2c.h>
37
38static const struct of_device_id ppc47x_of_bus[] __initconst = {
39	{ .compatible = "ibm,plb4", },
40	{ .compatible = "ibm,plb6", },
41	{ .compatible = "ibm,opb", },
42	{ .compatible = "ibm,ebc", },
43	{},
44};
45
46/* The EEPROM is missing and the default values are bogus.  This forces USB in
47 * to EHCI mode */
48static void quirk_ppc_currituck_usb_fixup(struct pci_dev *dev)
49{
50	if (of_machine_is_compatible("ibm,currituck")) {
51		pci_write_config_dword(dev, 0xe0, 0x0114231f);
52		pci_write_config_dword(dev, 0xe4, 0x00006c40);
53	}
54}
55DECLARE_PCI_FIXUP_HEADER(0x1033, 0x0035, quirk_ppc_currituck_usb_fixup);
56
57/* Akebono has an AVR microcontroller attached to the I2C bus
58 * which is used to power off/reset the system. */
59
60/* AVR I2C Commands */
61#define AVR_PWRCTL_CMD (0x26)
62
63/* Flags for the power control I2C commands */
64#define AVR_PWRCTL_PWROFF (0x01)
65#define AVR_PWRCTL_RESET (0x02)
66
67static struct i2c_client *avr_i2c_client;
68static void __noreturn avr_halt_system(int pwrctl_flags)
69{
70	/* Request the AVR to reset the system */
71	i2c_smbus_write_byte_data(avr_i2c_client,
72				  AVR_PWRCTL_CMD, pwrctl_flags);
73
74	/* Wait for system to be reset */
75	while (1)
76		;
77}
78
79static void avr_power_off_system(void)
80{
81	avr_halt_system(AVR_PWRCTL_PWROFF);
82}
83
84static void __noreturn avr_reset_system(char *cmd)
85{
86	avr_halt_system(AVR_PWRCTL_RESET);
87}
88
89static int avr_probe(struct i2c_client *client)
90{
91	avr_i2c_client = client;
92	ppc_md.restart = avr_reset_system;
93	pm_power_off = avr_power_off_system;
94	return 0;
95}
96
97static const struct i2c_device_id avr_id[] = {
98	{ "akebono-avr", 0 },
99	{ }
100};
101
102static struct i2c_driver avr_driver = {
103	.driver = {
104		.name = "akebono-avr",
105	},
106	.probe_new = avr_probe,
107	.id_table = avr_id,
108};
109
110static int __init ppc47x_device_probe(void)
111{
112	i2c_add_driver(&avr_driver);
113	of_platform_bus_probe(NULL, ppc47x_of_bus, NULL);
114
115	return 0;
116}
117machine_device_initcall(ppc47x, ppc47x_device_probe);
118
119static void __init ppc47x_init_irq(void)
120{
121	struct device_node *np;
122
123	/* Find top level interrupt controller */
124	for_each_node_with_property(np, "interrupt-controller") {
125		if (of_get_property(np, "interrupts", NULL) == NULL)
126			break;
127	}
128	if (np == NULL)
129		panic("Can't find top level interrupt controller");
130
131	/* Check type and do appropriate initialization */
132	if (of_device_is_compatible(np, "chrp,open-pic")) {
133		/* The MPIC driver will get everything it needs from the
134		 * device-tree, just pass 0 to all arguments
135		 */
136		struct mpic *mpic =
137			mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC     ");
138		BUG_ON(mpic == NULL);
139		mpic_init(mpic);
140		ppc_md.get_irq = mpic_get_irq;
141	} else
142		panic("Unrecognized top level interrupt controller");
143}
144
145#ifdef CONFIG_SMP
146static void smp_ppc47x_setup_cpu(int cpu)
147{
148	mpic_setup_this_cpu();
149}
150
151static int smp_ppc47x_kick_cpu(int cpu)
152{
153	struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
154	const u64 *spin_table_addr_prop;
155	u32 *spin_table;
156	extern void start_secondary_47x(void);
157
158	BUG_ON(cpunode == NULL);
159
160	/* Assume spin table. We could test for the enable-method in
161	 * the device-tree but currently there's little point as it's
162	 * our only supported method
163	 */
164	spin_table_addr_prop =
165		of_get_property(cpunode, "cpu-release-addr", NULL);
166
167	if (spin_table_addr_prop == NULL) {
168		pr_err("CPU%d: Can't start, missing cpu-release-addr !\n",
169		       cpu);
170		return 1;
171	}
172
173	/* Assume it's mapped as part of the linear mapping. This is a bit
174	 * fishy but will work fine for now
175	 *
176	 * XXX: Is there any reason to assume differently?
177	 */
178	spin_table = (u32 *)__va(*spin_table_addr_prop);
179	pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);
180
181	spin_table[3] = cpu;
182	smp_wmb();
183	spin_table[1] = __pa(start_secondary_47x);
184	mb();
185
186	return 0;
187}
188
189static struct smp_ops_t ppc47x_smp_ops = {
190	.probe		= smp_mpic_probe,
191	.message_pass	= smp_mpic_message_pass,
192	.setup_cpu	= smp_ppc47x_setup_cpu,
193	.kick_cpu	= smp_ppc47x_kick_cpu,
194	.give_timebase	= smp_generic_give_timebase,
195	.take_timebase	= smp_generic_take_timebase,
196};
197
198static void __init ppc47x_smp_init(void)
199{
200	if (mmu_has_feature(MMU_FTR_TYPE_47x))
201		smp_ops = &ppc47x_smp_ops;
202}
203
204#else /* CONFIG_SMP */
205static void __init ppc47x_smp_init(void) { }
206#endif /* CONFIG_SMP */
207
208static void __init ppc47x_setup_arch(void)
209{
210
211	/* No need to check the DMA config as we /know/ our windows are all of
212	 * RAM.  Lets hope that doesn't change */
213	swiotlb_detect_4g();
214
215	ppc47x_smp_init();
216}
217
218static int board_rev = -1;
219static int __init ppc47x_get_board_rev(void)
220{
221	int reg;
222	u8 *fpga;
223	struct device_node *np = NULL;
224
225	if (of_machine_is_compatible("ibm,currituck")) {
226		np = of_find_compatible_node(NULL, NULL, "ibm,currituck-fpga");
227		reg = 0;
228	} else if (of_machine_is_compatible("ibm,akebono")) {
229		np = of_find_compatible_node(NULL, NULL, "ibm,akebono-fpga");
230		reg = 2;
231	}
232
233	if (!np)
234		goto fail;
235
236	fpga = (u8 *) of_iomap(np, 0);
237	of_node_put(np);
238	if (!fpga)
239		goto fail;
240
241	board_rev = ioread8(fpga + reg) & 0x03;
242	pr_info("%s: Found board revision %d\n", __func__, board_rev);
243	iounmap(fpga);
244	return 0;
245
246fail:
247	pr_info("%s: Unable to find board revision\n", __func__);
248	return 0;
249}
250machine_arch_initcall(ppc47x, ppc47x_get_board_rev);
251
252/* Use USB controller should have been hardware swizzled but it wasn't :( */
253static void ppc47x_pci_irq_fixup(struct pci_dev *dev)
254{
255	if (dev->vendor == 0x1033 && (dev->device == 0x0035 ||
256				      dev->device == 0x00e0)) {
257		if (board_rev == 0) {
258			dev->irq = irq_create_mapping(NULL, 47);
259			pr_info("%s: Mapping irq %d\n", __func__, dev->irq);
260		} else if (board_rev == 2) {
261			dev->irq = irq_create_mapping(NULL, 49);
262			pr_info("%s: Mapping irq %d\n", __func__, dev->irq);
263		} else {
264			pr_alert("%s: Unknown board revision\n", __func__);
265		}
266	}
267}
268
269/*
270 * Called very early, MMU is off, device-tree isn't unflattened
271 */
272static int __init ppc47x_probe(void)
273{
274	if (of_machine_is_compatible("ibm,akebono"))
275		return 1;
276
277	if (of_machine_is_compatible("ibm,currituck")) {
278		ppc_md.pci_irq_fixup = ppc47x_pci_irq_fixup;
279		return 1;
280	}
281
282	return 0;
283}
284
285define_machine(ppc47x) {
286	.name			= "PowerPC 47x",
287	.probe			= ppc47x_probe,
288	.progress		= udbg_progress,
289	.init_IRQ		= ppc47x_init_irq,
290	.setup_arch		= ppc47x_setup_arch,
291	.restart		= ppc4xx_reset_system,
292	.calibrate_decr		= generic_calibrate_decr,
293};
294