acpi_pad: build only on X86
[linux-2.6/linux-acpi-2.6.git] / drivers / ieee1394 / init_ohci1394_dma.c
blobddaab6eb8acee1cab0b32fb578974caff59b723d
1 /*
2 * init_ohci1394_dma.c - Initializes physical DMA on all OHCI 1394 controllers
4 * Copyright (C) 2006-2007 Bernhard Kaindl <bk@suse.de>
6 * Derived from drivers/ieee1394/ohci1394.c and arch/x86/kernel/early-quirks.c
7 * this file has functions to:
8 * - scan the PCI very early on boot for all OHCI 1394-compliant controllers
9 * - reset and initialize them and make them join the IEEE1394 bus and
10 * - enable physical DMA on them to allow remote debugging
12 * All code and data is marked as __init and __initdata, respective as
13 * during boot, all OHCI1394 controllers may be claimed by the firewire
14 * stack and at this point, this code should not touch them anymore.
16 * To use physical DMA after the initialization of the firewire stack,
17 * be sure that the stack enables it and (re-)attach after the bus reset
18 * which may be caused by the firewire stack initialization.
20 * This program is free software; you can redistribute it and/or modify
21 * it under the terms of the GNU General Public License as published by
22 * the Free Software Foundation; either version 2 of the License, or
23 * (at your option) any later version.
25 * This program is distributed in the hope that it will be useful,
26 * but WITHOUT ANY WARRANTY; without even the implied warranty of
27 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
28 * GNU General Public License for more details.
30 * You should have received a copy of the GNU General Public License
31 * along with this program; if not, write to the Free Software Foundation,
32 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
35 #include <linux/interrupt.h> /* for ohci1394.h */
36 #include <linux/delay.h>
37 #include <linux/pci.h> /* for PCI defines */
38 #include <linux/init_ohci1394_dma.h>
39 #include <asm/pci-direct.h> /* for direct PCI config space access */
40 #include <asm/fixmap.h>
42 #include "ieee1394_types.h"
43 #include "ohci1394.h"
45 int __initdata init_ohci1394_dma_early;
47 /* Reads a PHY register of an OHCI-1394 controller */
48 static inline u8 __init get_phy_reg(struct ti_ohci *ohci, u8 addr)
50 int i;
51 quadlet_t r;
53 reg_write(ohci, OHCI1394_PhyControl, (addr << 8) | 0x00008000);
55 for (i = 0; i < OHCI_LOOP_COUNT; i++) {
56 if (reg_read(ohci, OHCI1394_PhyControl) & 0x80000000)
57 break;
58 mdelay(1);
60 r = reg_read(ohci, OHCI1394_PhyControl);
62 return (r & 0x00ff0000) >> 16;
65 /* Writes to a PHY register of an OHCI-1394 controller */
66 static inline void __init set_phy_reg(struct ti_ohci *ohci, u8 addr, u8 data)
68 int i;
70 reg_write(ohci, OHCI1394_PhyControl, (addr << 8) | data | 0x00004000);
72 for (i = 0; i < OHCI_LOOP_COUNT; i++) {
73 u32 r = reg_read(ohci, OHCI1394_PhyControl);
74 if (!(r & 0x00004000))
75 break;
76 mdelay(1);
80 /* Resets an OHCI-1394 controller (for sane state before initialization) */
81 static inline void __init init_ohci1394_soft_reset(struct ti_ohci *ohci) {
82 int i;
84 reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
86 for (i = 0; i < OHCI_LOOP_COUNT; i++) {
87 if (!(reg_read(ohci, OHCI1394_HCControlSet)
88 & OHCI1394_HCControl_softReset))
89 break;
90 mdelay(1);
94 /* Basic OHCI-1394 register and port inititalization */
95 static inline void __init init_ohci1394_initialize(struct ti_ohci *ohci)
97 quadlet_t bus_options;
98 int num_ports, i;
100 /* Put some defaults to these undefined bus options */
101 bus_options = reg_read(ohci, OHCI1394_BusOptions);
102 bus_options |= 0x60000000; /* Enable CMC and ISC */
103 bus_options &= ~0x00ff0000; /* XXX: Set cyc_clk_acc to zero for now */
104 bus_options &= ~0x18000000; /* Disable PMC and BMC */
105 reg_write(ohci, OHCI1394_BusOptions, bus_options);
107 /* Set the bus number */
108 reg_write(ohci, OHCI1394_NodeID, 0x0000ffc0);
110 /* Enable posted writes */
111 reg_write(ohci, OHCI1394_HCControlSet,
112 OHCI1394_HCControl_postedWriteEnable);
114 /* Clear link control register */
115 reg_write(ohci, OHCI1394_LinkControlClear, 0xffffffff);
117 /* enable phys */
118 reg_write(ohci, OHCI1394_LinkControlSet,
119 OHCI1394_LinkControl_RcvPhyPkt);
121 /* Don't accept phy packets into AR request context */
122 reg_write(ohci, OHCI1394_LinkControlClear, 0x00000400);
124 /* Clear the Isochonouys interrupt masks */
125 reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 0xffffffff);
126 reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 0xffffffff);
127 reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 0xffffffff);
128 reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 0xffffffff);
130 /* Accept asyncronous transfer requests from all nodes for now */
131 reg_write(ohci,OHCI1394_AsReqFilterHiSet, 0x80000000);
133 /* Specify asyncronous transfer retries */
134 reg_write(ohci, OHCI1394_ATRetries,
135 OHCI1394_MAX_AT_REQ_RETRIES |
136 (OHCI1394_MAX_AT_RESP_RETRIES<<4) |
137 (OHCI1394_MAX_PHYS_RESP_RETRIES<<8));
139 /* We don't want hardware swapping */
140 reg_write(ohci, OHCI1394_HCControlClear, OHCI1394_HCControl_noByteSwap);
142 /* Enable link */
143 reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_linkEnable);
145 /* If anything is connected to a port, make sure it is enabled */
146 num_ports = get_phy_reg(ohci, 2) & 0xf;
147 for (i = 0; i < num_ports; i++) {
148 unsigned int status;
150 set_phy_reg(ohci, 7, i);
151 status = get_phy_reg(ohci, 8);
153 if (status & 0x20)
154 set_phy_reg(ohci, 8, status & ~1);
159 * init_ohci1394_wait_for_busresets - wait until bus resets are completed
161 * OHCI1394 initialization itself and any device going on- or offline
162 * and any cable issue cause a IEEE1394 bus reset. The OHCI1394 spec
163 * specifies that physical DMA is disabled on each bus reset and it
164 * has to be enabled after each bus reset when needed. We resort
165 * to polling here because on early boot, we have no interrupts.
167 static inline void __init init_ohci1394_wait_for_busresets(struct ti_ohci *ohci)
169 int i, events;
171 for (i=0; i < 9; i++) {
172 mdelay(200);
173 events = reg_read(ohci, OHCI1394_IntEventSet);
174 if (events & OHCI1394_busReset)
175 reg_write(ohci, OHCI1394_IntEventClear,
176 OHCI1394_busReset);
181 * init_ohci1394_enable_physical_dma - Enable physical DMA for remote debugging
182 * This enables remote DMA access over IEEE1394 from every host for the low
183 * 4GB of address space. DMA accesses above 4GB are not available currently.
185 static inline void __init init_ohci1394_enable_physical_dma(struct ti_ohci *hci)
187 reg_write(hci, OHCI1394_PhyReqFilterHiSet, 0xffffffff);
188 reg_write(hci, OHCI1394_PhyReqFilterLoSet, 0xffffffff);
189 reg_write(hci, OHCI1394_PhyUpperBound, 0xffff0000);
193 * init_ohci1394_reset_and_init_dma - init controller and enable DMA
194 * This initializes the given controller and enables physical DMA engine in it.
196 static inline void __init init_ohci1394_reset_and_init_dma(struct ti_ohci *ohci)
198 /* Start off with a soft reset, clears everything to a sane state. */
199 init_ohci1394_soft_reset(ohci);
201 /* Accessing some registers without LPS enabled may cause lock up */
202 reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_LPS);
204 /* Disable and clear interrupts */
205 reg_write(ohci, OHCI1394_IntEventClear, 0xffffffff);
206 reg_write(ohci, OHCI1394_IntMaskClear, 0xffffffff);
208 mdelay(50); /* Wait 50msec to make sure we have full link enabled */
210 init_ohci1394_initialize(ohci);
212 * The initialization causes at least one IEEE1394 bus reset. Enabling
213 * physical DMA only works *after* *all* bus resets have calmed down:
215 init_ohci1394_wait_for_busresets(ohci);
217 /* We had to wait and do this now if we want to debug early problems */
218 init_ohci1394_enable_physical_dma(ohci);
222 * init_ohci1394_controller - Map the registers of the controller and init DMA
223 * This maps the registers of the specified controller and initializes it
225 static inline void __init init_ohci1394_controller(int num, int slot, int func)
227 unsigned long ohci_base;
228 struct ti_ohci ohci;
230 printk(KERN_INFO "init_ohci1394_dma: initializing OHCI-1394"
231 " at %02x:%02x.%x\n", num, slot, func);
233 ohci_base = read_pci_config(num, slot, func, PCI_BASE_ADDRESS_0+(0<<2))
234 & PCI_BASE_ADDRESS_MEM_MASK;
236 set_fixmap_nocache(FIX_OHCI1394_BASE, ohci_base);
238 ohci.registers = (void *)fix_to_virt(FIX_OHCI1394_BASE);
240 init_ohci1394_reset_and_init_dma(&ohci);
244 * debug_init_ohci1394_dma - scan for OHCI1394 controllers and init DMA on them
245 * Scans the whole PCI space for OHCI1394 controllers and inits DMA on them
247 void __init init_ohci1394_dma_on_all_controllers(void)
249 int num, slot, func;
251 if (!early_pci_allowed())
252 return;
254 /* Poor man's PCI discovery, the only thing we can do at early boot */
255 for (num = 0; num < 32; num++) {
256 for (slot = 0; slot < 32; slot++) {
257 for (func = 0; func < 8; func++) {
258 u32 class = read_pci_config(num,slot,func,
259 PCI_CLASS_REVISION);
260 if ((class == 0xffffffff))
261 continue; /* No device at this func */
263 if (class>>8 != PCI_CLASS_SERIAL_FIREWIRE_OHCI)
264 continue; /* Not an OHCI-1394 device */
266 init_ohci1394_controller(num, slot, func);
267 break; /* Assume one controller per device */
271 printk(KERN_INFO "init_ohci1394_dma: finished initializing OHCI DMA\n");
275 * setup_init_ohci1394_early - enables early OHCI1394 DMA initialization
277 static int __init setup_ohci1394_dma(char *opt)
279 if (!strcmp(opt, "early"))
280 init_ohci1394_dma_early = 1;
281 return 0;
284 /* passing ohci1394_dma=early on boot causes early OHCI1394 DMA initialization */
285 early_param("ohci1394_dma", setup_ohci1394_dma);