1 /*
2  * linux/arch/arm/common/it8152.c
3  *
4  * Copyright Compulab Ltd, 2002-2007
5  * Mike Rapoport <mike@compulab.co.il>
6  *
7  * The DMA bouncing part is taken from arch/arm/mach-ixp4xx/common-pci.c
8  * (see this file for respective copyrights)
9  *
10  * Thanks to Guennadi Liakhovetski <gl@dsa-ac.de> for IRQ enumberation
11  * and demux code.
12  *
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.
16  */
17 
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/init.h>
25 #include <linux/ioport.h>
26 #include <linux/irq.h>
27 #include <linux/io.h>
28 #include <linux/export.h>
29 
30 #include <asm/mach/pci.h>
31 #include <asm/hardware/it8152.h>
32 
33 #define MAX_SLOTS		21
34 
it8152_mask_irq(struct irq_data * d)35 static void it8152_mask_irq(struct irq_data *d)
36 {
37 	unsigned int irq = d->irq;
38 
39        if (irq >= IT8152_LD_IRQ(0)) {
40 	       __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) |
41 			    (1 << (irq - IT8152_LD_IRQ(0)))),
42 			    IT8152_INTC_LDCNIMR);
43        } else if (irq >= IT8152_LP_IRQ(0)) {
44 	       __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) |
45 			    (1 << (irq - IT8152_LP_IRQ(0)))),
46 			    IT8152_INTC_LPCNIMR);
47        } else if (irq >= IT8152_PD_IRQ(0)) {
48 	       __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) |
49 			    (1 << (irq - IT8152_PD_IRQ(0)))),
50 			    IT8152_INTC_PDCNIMR);
51        }
52 }
53 
it8152_unmask_irq(struct irq_data * d)54 static void it8152_unmask_irq(struct irq_data *d)
55 {
56 	unsigned int irq = d->irq;
57 
58        if (irq >= IT8152_LD_IRQ(0)) {
59 	       __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) &
60 			     ~(1 << (irq - IT8152_LD_IRQ(0)))),
61 			    IT8152_INTC_LDCNIMR);
62        } else if (irq >= IT8152_LP_IRQ(0)) {
63 	       __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) &
64 			     ~(1 << (irq - IT8152_LP_IRQ(0)))),
65 			    IT8152_INTC_LPCNIMR);
66        } else if (irq >= IT8152_PD_IRQ(0)) {
67 	       __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) &
68 			     ~(1 << (irq - IT8152_PD_IRQ(0)))),
69 			    IT8152_INTC_PDCNIMR);
70        }
71 }
72 
73 static struct irq_chip it8152_irq_chip = {
74 	.name		= "it8152",
75 	.irq_ack	= it8152_mask_irq,
76 	.irq_mask	= it8152_mask_irq,
77 	.irq_unmask	= it8152_unmask_irq,
78 };
79 
it8152_init_irq(void)80 void it8152_init_irq(void)
81 {
82 	int irq;
83 
84 	__raw_writel((0xffff), IT8152_INTC_PDCNIMR);
85 	__raw_writel((0), IT8152_INTC_PDCNIRR);
86 	__raw_writel((0xffff), IT8152_INTC_LPCNIMR);
87 	__raw_writel((0), IT8152_INTC_LPCNIRR);
88 	__raw_writel((0xffff), IT8152_INTC_LDCNIMR);
89 	__raw_writel((0), IT8152_INTC_LDCNIRR);
90 
91 	for (irq = IT8152_IRQ(0); irq <= IT8152_LAST_IRQ; irq++) {
92 		irq_set_chip_and_handler(irq, &it8152_irq_chip,
93 					 handle_level_irq);
94 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
95 	}
96 }
97 
it8152_irq_demux(unsigned int irq,struct irq_desc * desc)98 void it8152_irq_demux(unsigned int irq, struct irq_desc *desc)
99 {
100        int bits_pd, bits_lp, bits_ld;
101        int i;
102 
103        while (1) {
104 	       /* Read all */
105 	       bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
106 	       bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
107 	       bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
108 
109 	       /* Ack */
110 	       __raw_writel((~bits_pd), IT8152_INTC_PDCNIRR);
111 	       __raw_writel((~bits_lp), IT8152_INTC_LPCNIRR);
112 	       __raw_writel((~bits_ld), IT8152_INTC_LDCNIRR);
113 
114 	       if (!(bits_ld | bits_lp | bits_pd)) {
115 		       /* Re-read to guarantee, that there was a moment of
116 			  time, when they all three were 0. */
117 		       bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
118 		       bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
119 		       bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
120 		       if (!(bits_ld | bits_lp | bits_pd))
121 			       return;
122 	       }
123 
124 	       bits_pd &= ((1 << IT8152_PD_IRQ_COUNT) - 1);
125 	       while (bits_pd) {
126 		       i = __ffs(bits_pd);
127 		       generic_handle_irq(IT8152_PD_IRQ(i));
128 		       bits_pd &= ~(1 << i);
129 	       }
130 
131 	       bits_lp &= ((1 << IT8152_LP_IRQ_COUNT) - 1);
132 	       while (bits_lp) {
133 		       i = __ffs(bits_lp);
134 		       generic_handle_irq(IT8152_LP_IRQ(i));
135 		       bits_lp &= ~(1 << i);
136 	       }
137 
138 	       bits_ld &= ((1 << IT8152_LD_IRQ_COUNT) - 1);
139 	       while (bits_ld) {
140 		       i = __ffs(bits_ld);
141 		       generic_handle_irq(IT8152_LD_IRQ(i));
142 		       bits_ld &= ~(1 << i);
143 	       }
144        }
145 }
146 
147 /* mapping for on-chip devices */
it8152_pci_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)148 int __init it8152_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
149 {
150 	if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
151 	    (dev->device == PCI_DEVICE_ID_ITE_8152)) {
152 		if ((dev->class >> 8) == PCI_CLASS_MULTIMEDIA_AUDIO)
153 			return IT8152_AUDIO_INT;
154 		if ((dev->class >> 8) == PCI_CLASS_SERIAL_USB)
155 			return IT8152_USB_INT;
156 		if ((dev->class >> 8) == PCI_CLASS_SYSTEM_DMA)
157 			return IT8152_CDMA_INT;
158 	}
159 
160 	return 0;
161 }
162 
it8152_pci_dev_base_address(struct pci_bus * bus,unsigned int devfn)163 static unsigned long it8152_pci_dev_base_address(struct pci_bus *bus,
164 						 unsigned int devfn)
165 {
166 	unsigned long addr = 0;
167 
168 	if (bus->number == 0) {
169 			if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
170 				addr = (devfn << 8);
171 	} else
172 		addr = (bus->number << 16) | (devfn << 8);
173 
174 	return addr;
175 }
176 
it8152_pci_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)177 static int it8152_pci_read_config(struct pci_bus *bus,
178 				  unsigned int devfn, int where,
179 				  int size, u32 *value)
180 {
181 	unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
182 	u32 v;
183 	int shift;
184 
185 	shift = (where & 3);
186 
187 	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
188 	v = (__raw_readl(IT8152_PCI_CFG_DATA)  >> (8 * (shift)));
189 
190 	*value = v;
191 
192 	return PCIBIOS_SUCCESSFUL;
193 }
194 
it8152_pci_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)195 static int it8152_pci_write_config(struct pci_bus *bus,
196 				   unsigned int devfn, int where,
197 				   int size, u32 value)
198 {
199 	unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
200 	u32 v, vtemp, mask = 0;
201 	int shift;
202 
203 	if (size == 1)
204 		mask = 0xff;
205 	if (size == 2)
206 		mask = 0xffff;
207 
208 	shift = (where & 3);
209 
210 	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
211 	vtemp = __raw_readl(IT8152_PCI_CFG_DATA);
212 
213 	if (mask)
214 		vtemp &= ~(mask << (8 * shift));
215 	else
216 		vtemp = 0;
217 
218 	v = (value << (8 * shift));
219 	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
220 	__raw_writel((v | vtemp), IT8152_PCI_CFG_DATA);
221 
222 	return PCIBIOS_SUCCESSFUL;
223 }
224 
225 static struct pci_ops it8152_ops = {
226 	.read = it8152_pci_read_config,
227 	.write = it8152_pci_write_config,
228 };
229 
230 static struct resource it8152_io = {
231 	.name	= "IT8152 PCI I/O region",
232 	.flags	= IORESOURCE_IO,
233 };
234 
235 static struct resource it8152_mem = {
236 	.name	= "IT8152 PCI memory region",
237 	.start	= 0x10000000,
238 	.end	= 0x13e00000,
239 	.flags	= IORESOURCE_MEM,
240 };
241 
242 /*
243  * The following functions are needed for DMA bouncing.
244  * ITE8152 chip can address up to 64MByte, so all the devices
245  * connected to ITE8152 (PCI and USB) should have limited DMA window
246  */
it8152_needs_bounce(struct device * dev,dma_addr_t dma_addr,size_t size)247 static int it8152_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
248 {
249 	dev_dbg(dev, "%s: dma_addr %08x, size %08x\n",
250 		__func__, dma_addr, size);
251 	return (dma_addr + size - PHYS_OFFSET) >= SZ_64M;
252 }
253 
254 /*
255  * Setup DMA mask to 64MB on devices connected to ITE8152. Ignore all
256  * other devices.
257  */
it8152_pci_platform_notify(struct device * dev)258 static int it8152_pci_platform_notify(struct device *dev)
259 {
260 	if (dev->bus == &pci_bus_type) {
261 		if (dev->dma_mask)
262 			*dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
263 		dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
264 		dmabounce_register_dev(dev, 2048, 4096, it8152_needs_bounce);
265 	}
266 	return 0;
267 }
268 
it8152_pci_platform_notify_remove(struct device * dev)269 static int it8152_pci_platform_notify_remove(struct device *dev)
270 {
271 	if (dev->bus == &pci_bus_type)
272 		dmabounce_unregister_dev(dev);
273 
274 	return 0;
275 }
276 
dma_set_coherent_mask(struct device * dev,u64 mask)277 int dma_set_coherent_mask(struct device *dev, u64 mask)
278 {
279 	if (mask >= PHYS_OFFSET + SZ_64M - 1)
280 		return 0;
281 
282 	return -EIO;
283 }
284 
it8152_pci_setup(int nr,struct pci_sys_data * sys)285 int __init it8152_pci_setup(int nr, struct pci_sys_data *sys)
286 {
287 	it8152_io.start = IT8152_IO_BASE + 0x12000;
288 	it8152_io.end	= IT8152_IO_BASE + 0x12000 + 0x100000;
289 
290 	sys->mem_offset = 0x10000000;
291 	sys->io_offset  = IT8152_IO_BASE;
292 
293 	if (request_resource(&ioport_resource, &it8152_io)) {
294 		printk(KERN_ERR "PCI: unable to allocate IO region\n");
295 		goto err0;
296 	}
297 	if (request_resource(&iomem_resource, &it8152_mem)) {
298 		printk(KERN_ERR "PCI: unable to allocate memory region\n");
299 		goto err1;
300 	}
301 
302 	pci_add_resource_offset(&sys->resources, &it8152_io, sys->io_offset);
303 	pci_add_resource_offset(&sys->resources, &it8152_mem, sys->mem_offset);
304 
305 	if (platform_notify || platform_notify_remove) {
306 		printk(KERN_ERR "PCI: Can't use platform_notify\n");
307 		goto err2;
308 	}
309 
310 	platform_notify = it8152_pci_platform_notify;
311 	platform_notify_remove = it8152_pci_platform_notify_remove;
312 
313 	return 1;
314 
315 err2:
316 	release_resource(&it8152_io);
317 err1:
318 	release_resource(&it8152_mem);
319 err0:
320 	return -EBUSY;
321 }
322 
323 /* ITE bridge requires setting latency timer to avoid early bus access
324    termination by PCI bus master devices
325 */
pcibios_set_master(struct pci_dev * dev)326 void pcibios_set_master(struct pci_dev *dev)
327 {
328 	u8 lat;
329 
330 	/* no need to update on-chip OHCI controller */
331 	if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
332 	    (dev->device == PCI_DEVICE_ID_ITE_8152) &&
333 	    ((dev->class >> 8) == PCI_CLASS_SERIAL_USB))
334 		return;
335 
336 	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
337 	if (lat < 16)
338 		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
339 	else if (lat > pcibios_max_latency)
340 		lat = pcibios_max_latency;
341 	else
342 		return;
343 	printk(KERN_DEBUG "PCI: Setting latency timer of device %s to %d\n",
344 	       pci_name(dev), lat);
345 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
346 }
347 
348 
it8152_pci_scan_bus(int nr,struct pci_sys_data * sys)349 struct pci_bus * __init it8152_pci_scan_bus(int nr, struct pci_sys_data *sys)
350 {
351 	return pci_scan_root_bus(NULL, nr, &it8152_ops, sys, &sys->resources);
352 }
353 
354 EXPORT_SYMBOL(dma_set_coherent_mask);
355