xref: /openbmc/u-boot/arch/powerpc/cpu/mpc83xx/pci.c (revision dffceb4b)
1 /*
2  * Copyright (C) Freescale Semiconductor, Inc. 2007
3  *
4  * Author: Scott Wood <scottwood@freescale.com>,
5  * with some bits from older board-specific PCI initialization.
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <pci.h>
12 
13 #if defined(CONFIG_OF_LIBFDT)
14 #include <libfdt.h>
15 #include <fdt_support.h>
16 #endif
17 
18 #include <asm/mpc8349_pci.h>
19 
20 #define MAX_BUSES 2
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 
24 static struct pci_controller pci_hose[MAX_BUSES];
25 static int pci_num_buses;
26 
27 static void pci_init_bus(int bus, struct pci_region *reg)
28 {
29 	volatile immap_t *immr = (volatile immap_t *)CONFIG_SYS_IMMR;
30 	volatile pot83xx_t *pot = immr->ios.pot;
31 	volatile pcictrl83xx_t *pci_ctrl = &immr->pci_ctrl[bus];
32 	struct pci_controller *hose = &pci_hose[bus];
33 	u32 dev;
34 	u16 reg16;
35 	int i;
36 
37 	if (bus == 1)
38 		pot += 3;
39 
40 	/* Setup outbound translation windows */
41 	for (i = 0; i < 3; i++, reg++, pot++) {
42 		if (reg->size == 0)
43 			break;
44 
45 		hose->regions[i] = *reg;
46 		hose->region_count++;
47 
48 		pot->potar = reg->bus_start >> 12;
49 		pot->pobar = reg->phys_start >> 12;
50 		pot->pocmr = ~(reg->size - 1) >> 12;
51 
52 		if (reg->flags & PCI_REGION_IO)
53 			pot->pocmr |= POCMR_IO;
54 #ifdef CONFIG_83XX_PCI_STREAMING
55 		else if (reg->flags & PCI_REGION_PREFETCH)
56 			pot->pocmr |= POCMR_SE;
57 #endif
58 
59 		if (bus == 1)
60 			pot->pocmr |= POCMR_DST;
61 
62 		pot->pocmr |= POCMR_EN;
63 	}
64 
65 	/* Point inbound translation at RAM */
66 	pci_ctrl->pitar1 = 0;
67 	pci_ctrl->pibar1 = 0;
68 	pci_ctrl->piebar1 = 0;
69 	pci_ctrl->piwar1 = PIWAR_EN | PIWAR_PF | PIWAR_RTT_SNOOP |
70 			   PIWAR_WTT_SNOOP | (__ilog2(gd->ram_size - 1));
71 
72 	i = hose->region_count++;
73 	hose->regions[i].bus_start = 0;
74 	hose->regions[i].phys_start = 0;
75 	hose->regions[i].size = gd->ram_size;
76 	hose->regions[i].flags = PCI_REGION_MEM | PCI_REGION_SYS_MEMORY;
77 
78 	hose->first_busno = pci_last_busno() + 1;
79 	hose->last_busno = 0xff;
80 
81 	pci_setup_indirect(hose, CONFIG_SYS_IMMR + 0x8300 + bus * 0x80,
82 				 CONFIG_SYS_IMMR + 0x8304 + bus * 0x80);
83 
84 	pci_register_hose(hose);
85 
86 	/*
87 	 * Write to Command register
88 	 */
89 	reg16 = 0xff;
90 	dev = PCI_BDF(hose->first_busno, 0, 0);
91 	pci_hose_read_config_word(hose, dev, PCI_COMMAND, &reg16);
92 	reg16 |= PCI_COMMAND_SERR | PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY;
93 	pci_hose_write_config_word(hose, dev, PCI_COMMAND, reg16);
94 
95 	/*
96 	 * Clear non-reserved bits in status register.
97 	 */
98 	pci_hose_write_config_word(hose, dev, PCI_STATUS, 0xffff);
99 	pci_hose_write_config_byte(hose, dev, PCI_LATENCY_TIMER, 0x80);
100 	pci_hose_write_config_byte(hose, dev, PCI_CACHE_LINE_SIZE, 0x08);
101 
102 #ifdef CONFIG_PCI_SCAN_SHOW
103 	printf("PCI:   Bus Dev VenId DevId Class Int\n");
104 #endif
105 #ifndef CONFIG_PCISLAVE
106 	/*
107 	 * Hose scan.
108 	 */
109 	hose->last_busno = pci_hose_scan(hose);
110 #endif
111 }
112 
113 /*
114  * The caller must have already set OCCR, and the PCI_LAW BARs
115  * must have been set to cover all of the requested regions.
116  *
117  * If fewer than three regions are requested, then the region
118  * list is terminated with a region of size 0.
119  */
120 void mpc83xx_pci_init(int num_buses, struct pci_region **reg)
121 {
122 	volatile immap_t *immr = (volatile immap_t *)CONFIG_SYS_IMMR;
123 	int i;
124 
125 	if (num_buses > MAX_BUSES) {
126 		printf("%d PCI buses requested, %d supported\n",
127 		       num_buses, MAX_BUSES);
128 
129 		num_buses = MAX_BUSES;
130 	}
131 
132 	pci_num_buses = num_buses;
133 
134 	/*
135 	 * Release PCI RST Output signal.
136 	 * Power on to RST high must be at least 100 ms as per PCI spec.
137 	 * On warm boots only 1 ms is required, but we play it safe.
138 	 */
139 	udelay(100000);
140 
141 	for (i = 0; i < num_buses; i++)
142 		immr->pci_ctrl[i].gcr = 1;
143 
144 	/*
145 	 * RST high to first config access must be at least 2^25 cycles
146 	 * as per PCI spec.  This could be cut in half if we know we're
147 	 * running at 66MHz.  This could be insufficiently long if we're
148 	 * running the PCI bus at significantly less than 33MHz.
149 	 */
150 	udelay(1020000);
151 
152 	for (i = 0; i < num_buses; i++)
153 		pci_init_bus(i, reg[i]);
154 }
155 
156 #ifdef CONFIG_PCISLAVE
157 
158 #define PCI_FUNCTION_CONFIG	0x44
159 #define PCI_FUNCTION_CFG_LOCK	0x20
160 
161 /*
162  * Unlock the configuration bit so that the host system can begin booting
163  *
164  * This should be used after you have:
165  * 1) Called mpc83xx_pci_init()
166  * 2) Set up your inbound translation windows to the appropriate size
167  */
168 void mpc83xx_pcislave_unlock(int bus)
169 {
170 	struct pci_controller *hose = &pci_hose[bus];
171 	u32 dev;
172 	u16 reg16;
173 
174 	/* Unlock configuration lock in PCI function configuration register */
175 	dev = PCI_BDF(hose->first_busno, 0, 0);
176 	pci_hose_read_config_word (hose, dev, PCI_FUNCTION_CONFIG, &reg16);
177 	reg16 &= ~(PCI_FUNCTION_CFG_LOCK);
178 	pci_hose_write_config_word (hose, dev, PCI_FUNCTION_CONFIG, reg16);
179 
180 	/* The configuration bit is now unlocked, so we can scan the bus */
181 	hose->last_busno = pci_hose_scan(hose);
182 }
183 #endif
184 
185 #if defined(CONFIG_OF_LIBFDT)
186 void ft_pci_setup(void *blob, bd_t *bd)
187 {
188 	int nodeoffset;
189 	int tmp[2];
190 	const char *path;
191 
192 	if (pci_num_buses < 1)
193 		return;
194 
195 	nodeoffset = fdt_path_offset(blob, "/aliases");
196 	if (nodeoffset >= 0) {
197 		path = fdt_getprop(blob, nodeoffset, "pci0", NULL);
198 		if (path) {
199 			tmp[0] = cpu_to_be32(pci_hose[0].first_busno);
200 			tmp[1] = cpu_to_be32(pci_hose[0].last_busno);
201 			do_fixup_by_path(blob, path, "bus-range",
202 				&tmp, sizeof(tmp), 1);
203 
204 			tmp[0] = cpu_to_be32(gd->pci_clk);
205 			do_fixup_by_path(blob, path, "clock-frequency",
206 				&tmp, sizeof(tmp[0]), 1);
207 		}
208 
209 		if (pci_num_buses < 2)
210 			return;
211 
212 		path = fdt_getprop(blob, nodeoffset, "pci1", NULL);
213 		if (path) {
214 			tmp[0] = cpu_to_be32(pci_hose[1].first_busno);
215 			tmp[1] = cpu_to_be32(pci_hose[1].last_busno);
216 			do_fixup_by_path(blob, path, "bus-range",
217 				&tmp, sizeof(tmp), 1);
218 
219 			tmp[0] = cpu_to_be32(gd->pci_clk);
220 			do_fixup_by_path(blob, path, "clock-frequency",
221 				&tmp, sizeof(tmp[0]), 1);
222 		}
223 	}
224 }
225 #endif /* CONFIG_OF_LIBFDT */
226