xref: /openbmc/u-boot/arch/powerpc/cpu/mpc83xx/pci.c (revision fd0bc623)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) Freescale Semiconductor, Inc. 2007
4  *
5  * Author: Scott Wood <scottwood@freescale.com>,
6  * with some bits from older board-specific PCI initialization.
7  */
8 
9 #include <common.h>
10 #include <pci.h>
11 
12 #if defined(CONFIG_OF_LIBFDT)
13 #include <linux/libfdt.h>
14 #include <fdt_support.h>
15 #endif
16 
17 #include <asm/mpc8349_pci.h>
18 
19 #define MAX_BUSES 2
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 static struct pci_controller pci_hose[MAX_BUSES];
24 static int pci_num_buses;
25 
26 static void pci_init_bus(int bus, struct pci_region *reg)
27 {
28 	volatile immap_t *immr = (volatile immap_t *)CONFIG_SYS_IMMR;
29 	volatile pot83xx_t *pot = immr->ios.pot;
30 	volatile pcictrl83xx_t *pci_ctrl = &immr->pci_ctrl[bus];
31 	struct pci_controller *hose = &pci_hose[bus];
32 	u32 dev;
33 	u16 reg16;
34 	int i;
35 
36 	if (bus == 1)
37 		pot += 3;
38 
39 	/* Setup outbound translation windows */
40 	for (i = 0; i < 3; i++, reg++, pot++) {
41 		if (reg->size == 0)
42 			break;
43 
44 		hose->regions[i] = *reg;
45 		hose->region_count++;
46 
47 		pot->potar = reg->bus_start >> 12;
48 		pot->pobar = reg->phys_start >> 12;
49 		pot->pocmr = ~(reg->size - 1) >> 12;
50 
51 		if (reg->flags & PCI_REGION_IO)
52 			pot->pocmr |= POCMR_IO;
53 #ifdef CONFIG_83XX_PCI_STREAMING
54 		else if (reg->flags & PCI_REGION_PREFETCH)
55 			pot->pocmr |= POCMR_SE;
56 #endif
57 
58 		if (bus == 1)
59 			pot->pocmr |= POCMR_DST;
60 
61 		pot->pocmr |= POCMR_EN;
62 	}
63 
64 	/* Point inbound translation at RAM */
65 	pci_ctrl->pitar1 = 0;
66 	pci_ctrl->pibar1 = 0;
67 	pci_ctrl->piebar1 = 0;
68 	pci_ctrl->piwar1 = PIWAR_EN | PIWAR_PF | PIWAR_RTT_SNOOP |
69 			   PIWAR_WTT_SNOOP | (__ilog2(gd->ram_size - 1));
70 
71 	i = hose->region_count++;
72 	hose->regions[i].bus_start = 0;
73 	hose->regions[i].phys_start = 0;
74 	hose->regions[i].size = gd->ram_size;
75 	hose->regions[i].flags = PCI_REGION_MEM | PCI_REGION_SYS_MEMORY;
76 
77 	hose->first_busno = pci_last_busno() + 1;
78 	hose->last_busno = 0xff;
79 
80 	pci_setup_indirect(hose, CONFIG_SYS_IMMR + 0x8300 + bus * 0x80,
81 				 CONFIG_SYS_IMMR + 0x8304 + bus * 0x80);
82 
83 	pci_register_hose(hose);
84 
85 	/*
86 	 * Write to Command register
87 	 */
88 	reg16 = 0xff;
89 	dev = PCI_BDF(hose->first_busno, 0, 0);
90 	pci_hose_read_config_word(hose, dev, PCI_COMMAND, &reg16);
91 	reg16 |= PCI_COMMAND_SERR | PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
92 	pci_hose_write_config_word(hose, dev, PCI_COMMAND, reg16);
93 
94 	/*
95 	 * Clear non-reserved bits in status register.
96 	 */
97 	pci_hose_write_config_word(hose, dev, PCI_STATUS, 0xffff);
98 	pci_hose_write_config_byte(hose, dev, PCI_LATENCY_TIMER, 0x80);
99 	pci_hose_write_config_byte(hose, dev, PCI_CACHE_LINE_SIZE, 0x08);
100 
101 #ifdef CONFIG_PCI_SCAN_SHOW
102 	printf("PCI:   Bus Dev VenId DevId Class Int\n");
103 #endif
104 #ifndef CONFIG_PCISLAVE
105 	/*
106 	 * Hose scan.
107 	 */
108 	hose->last_busno = pci_hose_scan(hose);
109 #endif
110 }
111 
112 /*
113  * The caller must have already set OCCR, and the PCI_LAW BARs
114  * must have been set to cover all of the requested regions.
115  *
116  * If fewer than three regions are requested, then the region
117  * list is terminated with a region of size 0.
118  */
119 void mpc83xx_pci_init(int num_buses, struct pci_region **reg)
120 {
121 	volatile immap_t *immr = (volatile immap_t *)CONFIG_SYS_IMMR;
122 	int i;
123 
124 	if (num_buses > MAX_BUSES) {
125 		printf("%d PCI buses requested, %d supported\n",
126 		       num_buses, MAX_BUSES);
127 
128 		num_buses = MAX_BUSES;
129 	}
130 
131 	pci_num_buses = num_buses;
132 
133 	/*
134 	 * Release PCI RST Output signal.
135 	 * Power on to RST high must be at least 100 ms as per PCI spec.
136 	 * On warm boots only 1 ms is required, but we play it safe.
137 	 */
138 	udelay(100000);
139 
140 	for (i = 0; i < num_buses; i++)
141 		immr->pci_ctrl[i].gcr = 1;
142 
143 	/*
144 	 * RST high to first config access must be at least 2^25 cycles
145 	 * as per PCI spec.  This could be cut in half if we know we're
146 	 * running at 66MHz.  This could be insufficiently long if we're
147 	 * running the PCI bus at significantly less than 33MHz.
148 	 */
149 	udelay(1020000);
150 
151 	for (i = 0; i < num_buses; i++)
152 		pci_init_bus(i, reg[i]);
153 }
154 
155 #ifdef CONFIG_PCISLAVE
156 
157 #define PCI_FUNCTION_CONFIG	0x44
158 #define PCI_FUNCTION_CFG_LOCK	0x20
159 
160 /*
161  * Unlock the configuration bit so that the host system can begin booting
162  *
163  * This should be used after you have:
164  * 1) Called mpc83xx_pci_init()
165  * 2) Set up your inbound translation windows to the appropriate size
166  */
167 void mpc83xx_pcislave_unlock(int bus)
168 {
169 	struct pci_controller *hose = &pci_hose[bus];
170 	u32 dev;
171 	u16 reg16;
172 
173 	/* Unlock configuration lock in PCI function configuration register */
174 	dev = PCI_BDF(hose->first_busno, 0, 0);
175 	pci_hose_read_config_word (hose, dev, PCI_FUNCTION_CONFIG, &reg16);
176 	reg16 &= ~(PCI_FUNCTION_CFG_LOCK);
177 	pci_hose_write_config_word (hose, dev, PCI_FUNCTION_CONFIG, reg16);
178 
179 	/* The configuration bit is now unlocked, so we can scan the bus */
180 	hose->last_busno = pci_hose_scan(hose);
181 }
182 #endif
183 
184 #if defined(CONFIG_OF_LIBFDT)
185 void ft_pci_setup(void *blob, bd_t *bd)
186 {
187 	int nodeoffset;
188 	int tmp[2];
189 	const char *path;
190 
191 	if (pci_num_buses < 1)
192 		return;
193 
194 	nodeoffset = fdt_path_offset(blob, "/aliases");
195 	if (nodeoffset >= 0) {
196 		path = fdt_getprop(blob, nodeoffset, "pci0", NULL);
197 		if (path) {
198 			tmp[0] = cpu_to_be32(pci_hose[0].first_busno);
199 			tmp[1] = cpu_to_be32(pci_hose[0].last_busno);
200 			do_fixup_by_path(blob, path, "bus-range",
201 				&tmp, sizeof(tmp), 1);
202 
203 			tmp[0] = cpu_to_be32(gd->pci_clk);
204 			do_fixup_by_path(blob, path, "clock-frequency",
205 				&tmp, sizeof(tmp[0]), 1);
206 		}
207 
208 		if (pci_num_buses < 2)
209 			return;
210 
211 		path = fdt_getprop(blob, nodeoffset, "pci1", NULL);
212 		if (path) {
213 			tmp[0] = cpu_to_be32(pci_hose[1].first_busno);
214 			tmp[1] = cpu_to_be32(pci_hose[1].last_busno);
215 			do_fixup_by_path(blob, path, "bus-range",
216 				&tmp, sizeof(tmp), 1);
217 
218 			tmp[0] = cpu_to_be32(gd->pci_clk);
219 			do_fixup_by_path(blob, path, "clock-frequency",
220 				&tmp, sizeof(tmp[0]), 1);
221 		}
222 	}
223 }
224 #endif /* CONFIG_OF_LIBFDT */
225