Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 | /*
* Intel IXP4xx Queue Manager driver for Linux
*
* Copyright (C) 2007 Krzysztof Halasa <khc@pm.waw.pl>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*/
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <mach/qmgr.h>
#define DEBUG 0
struct qmgr_regs __iomem *qmgr_regs;
static struct resource *mem_res;
static spinlock_t qmgr_lock;
static u32 used_sram_bitmap[4]; /* 128 16-dword pages */
static void (*irq_handlers[HALF_QUEUES])(void *pdev);
static void *irq_pdevs[HALF_QUEUES];
void qmgr_set_irq(unsigned int queue, int src,
void (*handler)(void *pdev), void *pdev)
{
u32 __iomem *reg = &qmgr_regs->irqsrc[queue / 8]; /* 8 queues / u32 */
int bit = (queue % 8) * 4; /* 3 bits + 1 reserved bit per queue */
unsigned long flags;
src &= 7;
spin_lock_irqsave(&qmgr_lock, flags);
__raw_writel((__raw_readl(reg) & ~(7 << bit)) | (src << bit), reg);
irq_handlers[queue] = handler;
irq_pdevs[queue] = pdev;
spin_unlock_irqrestore(&qmgr_lock, flags);
}
static irqreturn_t qmgr_irq1(int irq, void *pdev)
{
int i;
u32 val = __raw_readl(&qmgr_regs->irqstat[0]);
__raw_writel(val, &qmgr_regs->irqstat[0]); /* ACK */
for (i = 0; i < HALF_QUEUES; i++)
if (val & (1 << i))
irq_handlers[i](irq_pdevs[i]);
return val ? IRQ_HANDLED : 0;
}
void qmgr_enable_irq(unsigned int queue)
{
unsigned long flags;
spin_lock_irqsave(&qmgr_lock, flags);
__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) | (1 << queue),
&qmgr_regs->irqen[0]);
spin_unlock_irqrestore(&qmgr_lock, flags);
}
void qmgr_disable_irq(unsigned int queue)
{
unsigned long flags;
spin_lock_irqsave(&qmgr_lock, flags);
__raw_writel(__raw_readl(&qmgr_regs->irqen[0]) & ~(1 << queue),
&qmgr_regs->irqen[0]);
spin_unlock_irqrestore(&qmgr_lock, flags);
}
static inline void shift_mask(u32 *mask)
{
mask[3] = mask[3] << 1 | mask[2] >> 31;
mask[2] = mask[2] << 1 | mask[1] >> 31;
mask[1] = mask[1] << 1 | mask[0] >> 31;
mask[0] <<= 1;
}
int qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */,
unsigned int nearly_empty_watermark,
unsigned int nearly_full_watermark)
{
u32 cfg, addr = 0, mask[4]; /* in 16-dwords */
int err;
if (queue >= HALF_QUEUES)
return -ERANGE;
if ((nearly_empty_watermark | nearly_full_watermark) & ~7)
return -EINVAL;
switch (len) {
case 16:
cfg = 0 << 24;
mask[0] = 0x1;
break;
case 32:
cfg = 1 << 24;
mask[0] = 0x3;
break;
case 64:
cfg = 2 << 24;
mask[0] = 0xF;
break;
case 128:
cfg = 3 << 24;
mask[0] = 0xFF;
break;
default:
return -EINVAL;
}
cfg |= nearly_empty_watermark << 26;
cfg |= nearly_full_watermark << 29;
len /= 16; /* in 16-dwords: 1, 2, 4 or 8 */
mask[1] = mask[2] = mask[3] = 0;
if (!try_module_get(THIS_MODULE))
return -ENODEV;
spin_lock_irq(&qmgr_lock);
if (__raw_readl(&qmgr_regs->sram[queue])) {
err = -EBUSY;
goto err;
}
while (1) {
if (!(used_sram_bitmap[0] & mask[0]) &&
!(used_sram_bitmap[1] & mask[1]) &&
!(used_sram_bitmap[2] & mask[2]) &&
!(used_sram_bitmap[3] & mask[3]))
break; /* found free space */
addr++;
shift_mask(mask);
if (addr + len > ARRAY_SIZE(qmgr_regs->sram)) {
printk(KERN_ERR "qmgr: no free SRAM space for"
" queue %i\n", queue);
err = -ENOMEM;
goto err;
}
}
used_sram_bitmap[0] |= mask[0];
used_sram_bitmap[1] |= mask[1];
used_sram_bitmap[2] |= mask[2];
used_sram_bitmap[3] |= mask[3];
__raw_writel(cfg | (addr << 14), &qmgr_regs->sram[queue]);
spin_unlock_irq(&qmgr_lock);
#if DEBUG
printk(KERN_DEBUG "qmgr: requested queue %i, addr = 0x%02X\n",
queue, addr);
#endif
return 0;
err:
spin_unlock_irq(&qmgr_lock);
module_put(THIS_MODULE);
return err;
}
void qmgr_release_queue(unsigned int queue)
{
u32 cfg, addr, mask[4];
BUG_ON(queue >= HALF_QUEUES); /* not in valid range */
spin_lock_irq(&qmgr_lock);
cfg = __raw_readl(&qmgr_regs->sram[queue]);
addr = (cfg >> 14) & 0xFF;
BUG_ON(!addr); /* not requested */
switch ((cfg >> 24) & 3) {
case 0: mask[0] = 0x1; break;
case 1: mask[0] = 0x3; break;
case 2: mask[0] = 0xF; break;
case 3: mask[0] = 0xFF; break;
}
mask[1] = mask[2] = mask[3] = 0;
while (addr--)
shift_mask(mask);
__raw_writel(0, &qmgr_regs->sram[queue]);
used_sram_bitmap[0] &= ~mask[0];
used_sram_bitmap[1] &= ~mask[1];
used_sram_bitmap[2] &= ~mask[2];
used_sram_bitmap[3] &= ~mask[3];
irq_handlers[queue] = NULL; /* catch IRQ bugs */
spin_unlock_irq(&qmgr_lock);
module_put(THIS_MODULE);
#if DEBUG
printk(KERN_DEBUG "qmgr: released queue %i\n", queue);
#endif
}
static int qmgr_init(void)
{
int i, err;
mem_res = request_mem_region(IXP4XX_QMGR_BASE_PHYS,
IXP4XX_QMGR_REGION_SIZE,
"IXP4xx Queue Manager");
if (mem_res == NULL)
return -EBUSY;
qmgr_regs = ioremap(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
if (qmgr_regs == NULL) {
err = -ENOMEM;
goto error_map;
}
/* reset qmgr registers */
for (i = 0; i < 4; i++) {
__raw_writel(0x33333333, &qmgr_regs->stat1[i]);
__raw_writel(0, &qmgr_regs->irqsrc[i]);
}
for (i = 0; i < 2; i++) {
__raw_writel(0, &qmgr_regs->stat2[i]);
__raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[i]); /* clear */
__raw_writel(0, &qmgr_regs->irqen[i]);
}
for (i = 0; i < QUEUES; i++)
__raw_writel(0, &qmgr_regs->sram[i]);
err = request_irq(IRQ_IXP4XX_QM1, qmgr_irq1, 0,
"IXP4xx Queue Manager", NULL);
if (err) {
printk(KERN_ERR "qmgr: failed to request IRQ%i\n",
IRQ_IXP4XX_QM1);
goto error_irq;
}
used_sram_bitmap[0] = 0xF; /* 4 first pages reserved for config */
spin_lock_init(&qmgr_lock);
printk(KERN_INFO "IXP4xx Queue Manager initialized.\n");
return 0;
error_irq:
iounmap(qmgr_regs);
error_map:
release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
return err;
}
static void qmgr_remove(void)
{
free_irq(IRQ_IXP4XX_QM1, NULL);
synchronize_irq(IRQ_IXP4XX_QM1);
iounmap(qmgr_regs);
release_mem_region(IXP4XX_QMGR_BASE_PHYS, IXP4XX_QMGR_REGION_SIZE);
}
module_init(qmgr_init);
module_exit(qmgr_remove);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Krzysztof Halasa");
EXPORT_SYMBOL(qmgr_regs);
EXPORT_SYMBOL(qmgr_set_irq);
EXPORT_SYMBOL(qmgr_enable_irq);
EXPORT_SYMBOL(qmgr_disable_irq);
EXPORT_SYMBOL(qmgr_request_queue);
EXPORT_SYMBOL(qmgr_release_queue);
|