avoid endless loops in lib/swiotlb.c
[wrt350n-kernel.git] / arch / arm / common / it8152.c
blob538262241483202545dad88ac247b427b9e6c3b6
1 /*
2 * linux/arch/arm/common/it8152.c
4 * Copyright Compulab Ltd, 2002-2007
5 * Mike Rapoport <mike@compulab.co.il>
7 * The DMA bouncing part is taken from arch/arm/mach-ixp4xx/common-pci.c
8 * (see this file for respective copyrights)
10 * Thanks to Guennadi Liakhovetski <gl@dsa-ac.de> for IRQ enumberation
11 * and demux code.
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/ptrace.h>
22 #include <linux/interrupt.h>
23 #include <linux/mm.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/ioport.h>
27 #include <linux/irq.h>
28 #include <linux/io.h>
30 #include <asm/mach/pci.h>
31 #include <asm/hardware/it8152.h>
33 #define MAX_SLOTS 21
35 static void it8152_mask_irq(unsigned int irq)
37 if (irq >= IT8152_LD_IRQ(0)) {
38 __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) |
39 (1 << (irq - IT8152_LD_IRQ(0)))),
40 IT8152_INTC_LDCNIMR);
41 } else if (irq >= IT8152_LP_IRQ(0)) {
42 __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) |
43 (1 << (irq - IT8152_LP_IRQ(0)))),
44 IT8152_INTC_LPCNIMR);
45 } else if (irq >= IT8152_PD_IRQ(0)) {
46 __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) |
47 (1 << (irq - IT8152_PD_IRQ(0)))),
48 IT8152_INTC_PDCNIMR);
52 static void it8152_unmask_irq(unsigned int irq)
54 if (irq >= IT8152_LD_IRQ(0)) {
55 __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) &
56 ~(1 << (irq - IT8152_LD_IRQ(0)))),
57 IT8152_INTC_LDCNIMR);
58 } else if (irq >= IT8152_LP_IRQ(0)) {
59 __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) &
60 ~(1 << (irq - IT8152_LP_IRQ(0)))),
61 IT8152_INTC_LPCNIMR);
62 } else if (irq >= IT8152_PD_IRQ(0)) {
63 __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) &
64 ~(1 << (irq - IT8152_PD_IRQ(0)))),
65 IT8152_INTC_PDCNIMR);
69 static inline void it8152_irq(int irq)
71 struct irq_desc *desc;
73 desc = irq_desc + irq;
74 desc_handle_irq(irq, desc);
77 static struct irq_chip it8152_irq_chip = {
78 .name = "it8152",
79 .ack = it8152_mask_irq,
80 .mask = it8152_mask_irq,
81 .unmask = it8152_unmask_irq,
84 void it8152_init_irq(void)
86 int irq;
88 __raw_writel((0xffff), IT8152_INTC_PDCNIMR);
89 __raw_writel((0), IT8152_INTC_PDCNIRR);
90 __raw_writel((0xffff), IT8152_INTC_LPCNIMR);
91 __raw_writel((0), IT8152_INTC_LPCNIRR);
92 __raw_writel((0xffff), IT8152_INTC_LDCNIMR);
93 __raw_writel((0), IT8152_INTC_LDCNIRR);
95 for (irq = IT8152_IRQ(0); irq <= IT8152_LAST_IRQ; irq++) {
96 set_irq_chip(irq, &it8152_irq_chip);
97 set_irq_handler(irq, handle_level_irq);
98 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
102 void it8152_irq_demux(unsigned int irq, struct irq_desc *desc)
104 int bits_pd, bits_lp, bits_ld;
105 int i;
107 while (1) {
108 /* Read all */
109 bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
110 bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
111 bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
113 /* Ack */
114 __raw_writel((~bits_pd), IT8152_INTC_PDCNIRR);
115 __raw_writel((~bits_lp), IT8152_INTC_LPCNIRR);
116 __raw_writel((~bits_ld), IT8152_INTC_LDCNIRR);
118 if (!(bits_ld | bits_lp | bits_pd)) {
119 /* Re-read to guarantee, that there was a moment of
120 time, when they all three were 0. */
121 bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
122 bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
123 if (!(bits_ld | bits_lp | bits_pd))
124 return;
127 bits_pd &= ((1 << IT8152_PD_IRQ_COUNT) - 1);
128 while (bits_pd) {
129 i = __ffs(bits_pd);
130 it8152_irq(IT8152_PD_IRQ(i));
131 bits_pd &= ~(1 << i);
134 bits_lp &= ((1 << IT8152_LP_IRQ_COUNT) - 1);
135 while (bits_lp) {
136 i = __ffs(bits_pd);
137 it8152_irq(IT8152_LP_IRQ(i));
138 bits_lp &= ~(1 << i);
141 bits_ld &= ((1 << IT8152_LD_IRQ_COUNT) - 1);
142 while (bits_ld) {
143 i = __ffs(bits_pd);
144 it8152_irq(IT8152_LD_IRQ(i));
145 bits_ld &= ~(1 << i);
150 /* mapping for on-chip devices */
151 int __init it8152_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
153 if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
154 (dev->device == PCI_DEVICE_ID_ITE_8152)) {
155 if ((dev->class >> 8) == PCI_CLASS_MULTIMEDIA_AUDIO)
156 return IT8152_AUDIO_INT;
157 if ((dev->class >> 8) == PCI_CLASS_SERIAL_USB)
158 return IT8152_USB_INT;
159 if ((dev->class >> 8) == PCI_CLASS_SYSTEM_DMA)
160 return IT8152_CDMA_INT;
163 return 0;
166 static unsigned long it8152_pci_dev_base_address(struct pci_bus *bus,
167 unsigned int devfn)
169 unsigned long addr = 0;
171 if (bus->number == 0) {
172 if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
173 addr = (devfn << 8);
174 } else
175 addr = (bus->number << 16) | (devfn << 8);
177 return addr;
180 static int it8152_pci_read_config(struct pci_bus *bus,
181 unsigned int devfn, int where,
182 int size, u32 *value)
184 unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
185 u32 v;
186 int shift;
188 shift = (where & 3);
190 __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
191 v = (__raw_readl(IT8152_PCI_CFG_DATA) >> (8 * (shift)));
193 *value = v;
195 return PCIBIOS_SUCCESSFUL;
198 static int it8152_pci_write_config(struct pci_bus *bus,
199 unsigned int devfn, int where,
200 int size, u32 value)
202 unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
203 u32 v, vtemp, mask = 0;
204 int shift;
206 if (size == 1)
207 mask = 0xff;
208 if (size == 2)
209 mask = 0xffff;
211 shift = (where & 3);
213 __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
214 vtemp = __raw_readl(IT8152_PCI_CFG_DATA);
216 if (mask)
217 vtemp &= ~(mask << (8 * shift));
218 else
219 vtemp = 0;
221 v = (value << (8 * shift));
222 __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
223 __raw_writel((v | vtemp), IT8152_PCI_CFG_DATA);
225 return PCIBIOS_SUCCESSFUL;
228 static struct pci_ops it8152_ops = {
229 .read = it8152_pci_read_config,
230 .write = it8152_pci_write_config,
233 static struct resource it8152_io = {
234 .name = "IT8152 PCI I/O region",
235 .flags = IORESOURCE_IO,
238 static struct resource it8152_mem = {
239 .name = "IT8152 PCI memory region",
240 .start = 0x10000000,
241 .end = 0x13e00000,
242 .flags = IORESOURCE_MEM,
246 * The following functions are needed for DMA bouncing.
247 * ITE8152 chip can addrees up to 64MByte, so all the devices
248 * connected to ITE8152 (PCI and USB) should have limited DMA window
252 * Setup DMA mask to 64MB on devices connected to ITE8152. Ignore all
253 * other devices.
255 static int it8152_pci_platform_notify(struct device *dev)
257 if (dev->bus == &pci_bus_type) {
258 if (dev->dma_mask)
259 *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
260 dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
261 dmabounce_register_dev(dev, 2048, 4096);
263 return 0;
266 static int it8152_pci_platform_notify_remove(struct device *dev)
268 if (dev->bus == &pci_bus_type)
269 dmabounce_unregister_dev(dev);
271 return 0;
274 int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
276 dev_dbg(dev, "%s: dma_addr %08x, size %08x\n",
277 __func__, dma_addr, size);
278 return (dev->bus == &pci_bus_type) &&
279 ((dma_addr + size - PHYS_OFFSET) >= SZ_64M);
283 * We override these so we properly do dmabounce otherwise drivers
284 * are able to set the dma_mask to 0xffffffff and we can no longer
285 * trap bounces. :(
287 * We just return true on everyhing except for < 64MB in which case
288 * we will fail miseralby and die since we can't handle that case.
290 int pci_set_dma_mask(struct pci_dev *dev, u64 mask)
292 dev_dbg(&dev->dev, "%s: %llx\n", __func__, mask);
293 if (mask >= PHYS_OFFSET + SZ_64M - 1)
294 return 0;
296 return -EIO;
300 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
302 dev_dbg(&dev->dev, "%s: %llx\n", __func__, mask);
303 if (mask >= PHYS_OFFSET + SZ_64M - 1)
304 return 0;
306 return -EIO;
309 int __init it8152_pci_setup(int nr, struct pci_sys_data *sys)
311 it8152_io.start = IT8152_IO_BASE + 0x12000;
312 it8152_io.end = IT8152_IO_BASE + 0x12000 + 0x100000;
314 sys->mem_offset = 0x10000000;
315 sys->io_offset = IT8152_IO_BASE;
317 if (request_resource(&ioport_resource, &it8152_io)) {
318 printk(KERN_ERR "PCI: unable to allocate IO region\n");
319 goto err0;
321 if (request_resource(&iomem_resource, &it8152_mem)) {
322 printk(KERN_ERR "PCI: unable to allocate memory region\n");
323 goto err1;
326 sys->resource[0] = &it8152_io;
327 sys->resource[1] = &it8152_mem;
329 if (platform_notify || platform_notify_remove) {
330 printk(KERN_ERR "PCI: Can't use platform_notify\n");
331 goto err2;
334 platform_notify = it8152_pci_platform_notify;
335 platform_notify_remove = it8152_pci_platform_notify_remove;
337 return 1;
339 err2:
340 release_resource(&it8152_io);
341 err1:
342 release_resource(&it8152_mem);
343 err0:
344 return -EBUSY;
348 * If we set up a device for bus mastering, we need to check the latency
349 * timer as we don't have even crappy BIOSes to set it properly.
350 * The implementation is from arch/i386/pci/i386.c
352 unsigned int pcibios_max_latency = 255;
354 void pcibios_set_master(struct pci_dev *dev)
356 u8 lat;
358 /* no need to update on-chip OHCI controller */
359 if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
360 (dev->device == PCI_DEVICE_ID_ITE_8152) &&
361 ((dev->class >> 8) == PCI_CLASS_SERIAL_USB))
362 return;
364 pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
365 if (lat < 16)
366 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
367 else if (lat > pcibios_max_latency)
368 lat = pcibios_max_latency;
369 else
370 return;
371 printk(KERN_DEBUG "PCI: Setting latency timer of device %s to %d\n",
372 pci_name(dev), lat);
373 pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
377 struct pci_bus * __init it8152_pci_scan_bus(int nr, struct pci_sys_data *sys)
379 return pci_scan_bus(nr, &it8152_ops, sys);