1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * MPC85xx setup and early boot code plus other random bits.
4  *
5  * Maintained by Kumar Gala (see MAINTAINERS for contact information)
6  *
7  * Copyright 2005, 2011-2012 Freescale Semiconductor Inc.
8  */
9 
10 #include <linux/stddef.h>
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/errno.h>
14 #include <linux/reboot.h>
15 #include <linux/pci.h>
16 #include <linux/kdev_t.h>
17 #include <linux/major.h>
18 #include <linux/console.h>
19 #include <linux/delay.h>
20 #include <linux/seq_file.h>
21 #include <linux/initrd.h>
22 #include <linux/interrupt.h>
23 #include <linux/fsl_devices.h>
24 #include <linux/of_platform.h>
25 #include <linux/pgtable.h>
26 
27 #include <asm/page.h>
28 #include <linux/atomic.h>
29 #include <asm/time.h>
30 #include <asm/io.h>
31 #include <asm/machdep.h>
32 #include <asm/ipic.h>
33 #include <asm/pci-bridge.h>
34 #include <asm/irq.h>
35 #include <mm/mmu_decl.h>
36 #include <asm/prom.h>
37 #include <asm/udbg.h>
38 #include <asm/mpic.h>
39 #include <asm/i8259.h>
40 
41 #include <sysdev/fsl_soc.h>
42 #include <sysdev/fsl_pci.h>
43 
44 #include "mpc85xx.h"
45 
46 /*
47  * The CDS board contains an FPGA/CPLD called "Cadmus", which collects
48  * various logic and performs system control functions.
49  * Here is the FPGA/CPLD register map.
50  */
51 struct cadmus_reg {
52 	u8 cm_ver;		/* Board version */
53 	u8 cm_csr;		/* General control/status */
54 	u8 cm_rst;		/* Reset control */
55 	u8 cm_hsclk;	/* High speed clock */
56 	u8 cm_hsxclk;	/* High speed clock extended */
57 	u8 cm_led;		/* LED data */
58 	u8 cm_pci;		/* PCI control/status */
59 	u8 cm_dma;		/* DMA control */
60 	u8 res[248];	/* Total 256 bytes */
61 };
62 
63 static struct cadmus_reg *cadmus;
64 
65 #ifdef CONFIG_PCI
66 
67 #define ARCADIA_HOST_BRIDGE_IDSEL	17
68 #define ARCADIA_2ND_BRIDGE_IDSEL	3
69 
mpc85xx_exclude_device(struct pci_controller * hose,u_char bus,u_char devfn)70 static int mpc85xx_exclude_device(struct pci_controller *hose,
71 				  u_char bus, u_char devfn)
72 {
73 	/* We explicitly do not go past the Tundra 320 Bridge */
74 	if ((bus == 1) && (PCI_SLOT(devfn) == ARCADIA_2ND_BRIDGE_IDSEL))
75 		return PCIBIOS_DEVICE_NOT_FOUND;
76 	if ((bus == 0) && (PCI_SLOT(devfn) == ARCADIA_2ND_BRIDGE_IDSEL))
77 		return PCIBIOS_DEVICE_NOT_FOUND;
78 	else
79 		return PCIBIOS_SUCCESSFUL;
80 }
81 
mpc85xx_cds_restart(struct notifier_block * this,unsigned long mode,void * cmd)82 static int mpc85xx_cds_restart(struct notifier_block *this,
83 			       unsigned long mode, void *cmd)
84 {
85 	struct pci_dev *dev;
86 	u_char tmp;
87 
88 	if ((dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686,
89 					NULL))) {
90 
91 		/* Use the VIA Super Southbridge to force a PCI reset */
92 		pci_read_config_byte(dev, 0x47, &tmp);
93 		pci_write_config_byte(dev, 0x47, tmp | 1);
94 
95 		/* Flush the outbound PCI write queues */
96 		pci_read_config_byte(dev, 0x47, &tmp);
97 
98 		/*
99 		 *  At this point, the hardware reset should have triggered.
100 		 *  However, if it doesn't work for some mysterious reason,
101 		 *  just fall through to the default reset below.
102 		 */
103 
104 		pci_dev_put(dev);
105 	}
106 
107 	/*
108 	 *  If we can't find the VIA chip (maybe the P2P bridge is
109 	 *  disabled) or the VIA chip reset didn't work, just return
110 	 *  and let default reset sequence happen.
111 	 */
112 	return NOTIFY_DONE;
113 }
114 
mpc85xx_cds_restart_register(void)115 static int mpc85xx_cds_restart_register(void)
116 {
117 	static struct notifier_block restart_handler;
118 
119 	restart_handler.notifier_call = mpc85xx_cds_restart;
120 	restart_handler.priority = 192;
121 
122 	return register_restart_handler(&restart_handler);
123 }
124 machine_arch_initcall(mpc85xx_cds, mpc85xx_cds_restart_register);
125 
126 
mpc85xx_cds_pci_irq_fixup(struct pci_dev * dev)127 static void __init mpc85xx_cds_pci_irq_fixup(struct pci_dev *dev)
128 {
129 	u_char c;
130 	if (dev->vendor == PCI_VENDOR_ID_VIA) {
131 		switch (dev->device) {
132 		case PCI_DEVICE_ID_VIA_82C586_1:
133 			/*
134 			 * U-Boot does not set the enable bits
135 			 * for the IDE device. Force them on here.
136 			 */
137 			pci_read_config_byte(dev, 0x40, &c);
138 			c |= 0x03; /* IDE: Chip Enable Bits */
139 			pci_write_config_byte(dev, 0x40, c);
140 
141 			/*
142 			 * Since only primary interface works, force the
143 			 * IDE function to standard primary IDE interrupt
144 			 * w/ 8259 offset
145 			 */
146 			dev->irq = 14;
147 			pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
148 			break;
149 		/*
150 		 * Force legacy USB interrupt routing
151 		 */
152 		case PCI_DEVICE_ID_VIA_82C586_2:
153 		/* There are two USB controllers.
154 		 * Identify them by functon number
155 		 */
156 			if (PCI_FUNC(dev->devfn) == 3)
157 				dev->irq = 11;
158 			else
159 				dev->irq = 10;
160 			pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
161 		default:
162 			break;
163 		}
164 	}
165 }
166 
skip_fake_bridge(struct pci_dev * dev)167 static void skip_fake_bridge(struct pci_dev *dev)
168 {
169 	/* Make it an error to skip the fake bridge
170 	 * in pci_setup_device() in probe.c */
171 	dev->hdr_type = 0x7f;
172 }
173 DECLARE_PCI_FIXUP_EARLY(0x1957, 0x3fff, skip_fake_bridge);
174 DECLARE_PCI_FIXUP_EARLY(0x3fff, 0x1957, skip_fake_bridge);
175 DECLARE_PCI_FIXUP_EARLY(0xff3f, 0x5719, skip_fake_bridge);
176 
177 #define PCI_DEVICE_ID_IDT_TSI310	0x01a7
178 
179 /*
180  * Fix Tsi310 PCI-X bridge resource.
181  * Force the bridge to open a window from 0x0000-0x1fff in PCI I/O space.
182  * This allows legacy I/O(i8259, etc) on the VIA southbridge to be accessed.
183  */
mpc85xx_cds_fixup_bus(struct pci_bus * bus)184 void mpc85xx_cds_fixup_bus(struct pci_bus *bus)
185 {
186 	struct pci_dev *dev = bus->self;
187 	struct resource *res = bus->resource[0];
188 
189 	if (dev != NULL &&
190 	    dev->vendor == PCI_VENDOR_ID_IBM &&
191 	    dev->device == PCI_DEVICE_ID_IDT_TSI310) {
192 		if (res) {
193 			res->start = 0;
194 			res->end   = 0x1fff;
195 			res->flags = IORESOURCE_IO;
196 			pr_info("mpc85xx_cds: PCI bridge resource fixup applied\n");
197 			pr_info("mpc85xx_cds: %pR\n", res);
198 		}
199 	}
200 
201 	fsl_pcibios_fixup_bus(bus);
202 }
203 
204 #ifdef CONFIG_PPC_I8259
mpc85xx_8259_cascade_handler(struct irq_desc * desc)205 static void mpc85xx_8259_cascade_handler(struct irq_desc *desc)
206 {
207 	unsigned int cascade_irq = i8259_irq();
208 
209 	if (cascade_irq)
210 		/* handle an interrupt from the 8259 */
211 		generic_handle_irq(cascade_irq);
212 
213 	/* check for any interrupts from the shared IRQ line */
214 	handle_fasteoi_irq(desc);
215 }
216 
mpc85xx_8259_cascade_action(int irq,void * dev_id)217 static irqreturn_t mpc85xx_8259_cascade_action(int irq, void *dev_id)
218 {
219 	return IRQ_HANDLED;
220 }
221 #endif /* PPC_I8259 */
222 #endif /* CONFIG_PCI */
223 
mpc85xx_cds_pic_init(void)224 static void __init mpc85xx_cds_pic_init(void)
225 {
226 	struct mpic *mpic;
227 	mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN,
228 			0, 256, " OpenPIC  ");
229 	BUG_ON(mpic == NULL);
230 	mpic_init(mpic);
231 }
232 
233 #if defined(CONFIG_PPC_I8259) && defined(CONFIG_PCI)
mpc85xx_cds_8259_attach(void)234 static int mpc85xx_cds_8259_attach(void)
235 {
236 	int ret;
237 	struct device_node *np = NULL;
238 	struct device_node *cascade_node = NULL;
239 	int cascade_irq;
240 
241 	/* Initialize the i8259 controller */
242 	for_each_node_by_type(np, "interrupt-controller")
243 		if (of_device_is_compatible(np, "chrp,iic")) {
244 			cascade_node = np;
245 			break;
246 		}
247 
248 	if (cascade_node == NULL) {
249 		printk(KERN_DEBUG "Could not find i8259 PIC\n");
250 		return -ENODEV;
251 	}
252 
253 	cascade_irq = irq_of_parse_and_map(cascade_node, 0);
254 	if (!cascade_irq) {
255 		printk(KERN_ERR "Failed to map cascade interrupt\n");
256 		return -ENXIO;
257 	}
258 
259 	i8259_init(cascade_node, 0);
260 	of_node_put(cascade_node);
261 
262 	/*
263 	 *  Hook the interrupt to make sure desc->action is never NULL.
264 	 *  This is required to ensure that the interrupt does not get
265 	 *  disabled when the last user of the shared IRQ line frees their
266 	 *  interrupt.
267 	 */
268 	ret = request_irq(cascade_irq, mpc85xx_8259_cascade_action,
269 			  IRQF_SHARED | IRQF_NO_THREAD, "8259 cascade",
270 			  cascade_node);
271 	if (ret) {
272 		printk(KERN_ERR "Failed to setup cascade interrupt\n");
273 		return ret;
274 	}
275 
276 	/* Success. Connect our low-level cascade handler. */
277 	irq_set_handler(cascade_irq, mpc85xx_8259_cascade_handler);
278 
279 	return 0;
280 }
281 machine_device_initcall(mpc85xx_cds, mpc85xx_cds_8259_attach);
282 
283 #endif /* CONFIG_PPC_I8259 */
284 
mpc85xx_cds_pci_assign_primary(void)285 static void mpc85xx_cds_pci_assign_primary(void)
286 {
287 #ifdef CONFIG_PCI
288 	struct device_node *np;
289 
290 	if (fsl_pci_primary)
291 		return;
292 
293 	/*
294 	 * MPC85xx_CDS has ISA bridge but unfortunately there is no
295 	 * isa node in device tree. We now looking for i8259 node as
296 	 * a workaround for such a broken device tree. This routine
297 	 * is for complying to all device trees.
298 	 */
299 	np = of_find_node_by_name(NULL, "i8259");
300 	while ((fsl_pci_primary = of_get_parent(np))) {
301 		of_node_put(np);
302 		np = fsl_pci_primary;
303 
304 		if ((of_device_is_compatible(np, "fsl,mpc8540-pci") ||
305 		    of_device_is_compatible(np, "fsl,mpc8548-pcie")) &&
306 		    of_device_is_available(np))
307 			return;
308 	}
309 #endif
310 }
311 
312 /*
313  * Setup the architecture
314  */
mpc85xx_cds_setup_arch(void)315 static void __init mpc85xx_cds_setup_arch(void)
316 {
317 	struct device_node *np;
318 	int cds_pci_slot;
319 
320 	if (ppc_md.progress)
321 		ppc_md.progress("mpc85xx_cds_setup_arch()", 0);
322 
323 	np = of_find_compatible_node(NULL, NULL, "fsl,mpc8548cds-fpga");
324 	if (!np) {
325 		pr_err("Could not find FPGA node.\n");
326 		return;
327 	}
328 
329 	cadmus = of_iomap(np, 0);
330 	of_node_put(np);
331 	if (!cadmus) {
332 		pr_err("Fail to map FPGA area.\n");
333 		return;
334 	}
335 
336 	if (ppc_md.progress) {
337 		char buf[40];
338 		cds_pci_slot = ((in_8(&cadmus->cm_csr) >> 6) & 0x3) + 1;
339 		snprintf(buf, 40, "CDS Version = 0x%x in slot %d\n",
340 				in_8(&cadmus->cm_ver), cds_pci_slot);
341 		ppc_md.progress(buf, 0);
342 	}
343 
344 #ifdef CONFIG_PCI
345 	ppc_md.pci_irq_fixup = mpc85xx_cds_pci_irq_fixup;
346 	ppc_md.pci_exclude_device = mpc85xx_exclude_device;
347 #endif
348 
349 	mpc85xx_cds_pci_assign_primary();
350 	fsl_pci_assign_primary();
351 }
352 
mpc85xx_cds_show_cpuinfo(struct seq_file * m)353 static void mpc85xx_cds_show_cpuinfo(struct seq_file *m)
354 {
355 	uint pvid, svid, phid1;
356 
357 	pvid = mfspr(SPRN_PVR);
358 	svid = mfspr(SPRN_SVR);
359 
360 	seq_printf(m, "Vendor\t\t: Freescale Semiconductor\n");
361 	seq_printf(m, "Machine\t\t: MPC85xx CDS (0x%x)\n",
362 			in_8(&cadmus->cm_ver));
363 	seq_printf(m, "PVR\t\t: 0x%x\n", pvid);
364 	seq_printf(m, "SVR\t\t: 0x%x\n", svid);
365 
366 	/* Display cpu Pll setting */
367 	phid1 = mfspr(SPRN_HID1);
368 	seq_printf(m, "PLL setting\t: 0x%x\n", ((phid1 >> 24) & 0x3f));
369 }
370 
371 
372 /*
373  * Called very early, device-tree isn't unflattened
374  */
mpc85xx_cds_probe(void)375 static int __init mpc85xx_cds_probe(void)
376 {
377 	return of_machine_is_compatible("MPC85xxCDS");
378 }
379 
380 machine_arch_initcall(mpc85xx_cds, mpc85xx_common_publish_devices);
381 
define_machine(mpc85xx_cds)382 define_machine(mpc85xx_cds) {
383 	.name		= "MPC85xx CDS",
384 	.probe		= mpc85xx_cds_probe,
385 	.setup_arch	= mpc85xx_cds_setup_arch,
386 	.init_IRQ	= mpc85xx_cds_pic_init,
387 	.show_cpuinfo	= mpc85xx_cds_show_cpuinfo,
388 	.get_irq	= mpic_get_irq,
389 #ifdef CONFIG_PCI
390 	.pcibios_fixup_bus	= mpc85xx_cds_fixup_bus,
391 	.pcibios_fixup_phb      = fsl_pcibios_fixup_phb,
392 #endif
393 	.calibrate_decr = generic_calibrate_decr,
394 	.progress	= udbg_progress,
395 };
396