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path: root/drivers/soc/ixp4xx/ixp4xx-qmgr.c
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Diffstat (limited to 'drivers/soc/ixp4xx/ixp4xx-qmgr.c')
-rw-r--r--drivers/soc/ixp4xx/ixp4xx-qmgr.c488
1 files changed, 488 insertions, 0 deletions
diff --git a/drivers/soc/ixp4xx/ixp4xx-qmgr.c b/drivers/soc/ixp4xx/ixp4xx-qmgr.c
new file mode 100644
index 000000000000..13a8a13c9b01
--- /dev/null
+++ b/drivers/soc/ixp4xx/ixp4xx-qmgr.c
@@ -0,0 +1,488 @@
+/*
+ * 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 <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/soc/ixp4xx/qmgr.h>
+
+static struct qmgr_regs __iomem *qmgr_regs;
+static int qmgr_irq_1;
+static int qmgr_irq_2;
+static spinlock_t qmgr_lock;
+static u32 used_sram_bitmap[4]; /* 128 16-dword pages */
+static void (*irq_handlers[QUEUES])(void *pdev);
+static void *irq_pdevs[QUEUES];
+
+#if DEBUG_QMGR
+char qmgr_queue_descs[QUEUES][32];
+#endif
+
+void qmgr_put_entry(unsigned int queue, u32 val)
+{
+#if DEBUG_QMGR
+ BUG_ON(!qmgr_queue_descs[queue]); /* not yet requested */
+
+ printk(KERN_DEBUG "Queue %s(%i) put %X\n",
+ qmgr_queue_descs[queue], queue, val);
+#endif
+ __raw_writel(val, &qmgr_regs->acc[queue][0]);
+}
+
+u32 qmgr_get_entry(unsigned int queue)
+{
+ u32 val;
+ val = __raw_readl(&qmgr_regs->acc[queue][0]);
+#if DEBUG_QMGR
+ BUG_ON(!qmgr_queue_descs[queue]); /* not yet requested */
+
+ printk(KERN_DEBUG "Queue %s(%i) get %X\n",
+ qmgr_queue_descs[queue], queue, val);
+#endif
+ return val;
+}
+
+static int __qmgr_get_stat1(unsigned int queue)
+{
+ return (__raw_readl(&qmgr_regs->stat1[queue >> 3])
+ >> ((queue & 7) << 2)) & 0xF;
+}
+
+static int __qmgr_get_stat2(unsigned int queue)
+{
+ BUG_ON(queue >= HALF_QUEUES);
+ return (__raw_readl(&qmgr_regs->stat2[queue >> 4])
+ >> ((queue & 0xF) << 1)) & 0x3;
+}
+
+/**
+ * qmgr_stat_empty() - checks if a hardware queue is empty
+ * @queue: queue number
+ *
+ * Returns non-zero value if the queue is empty.
+ */
+int qmgr_stat_empty(unsigned int queue)
+{
+ BUG_ON(queue >= HALF_QUEUES);
+ return __qmgr_get_stat1(queue) & QUEUE_STAT1_EMPTY;
+}
+
+/**
+ * qmgr_stat_below_low_watermark() - checks if a queue is below low watermark
+ * @queue: queue number
+ *
+ * Returns non-zero value if the queue is below low watermark.
+ */
+int qmgr_stat_below_low_watermark(unsigned int queue)
+{
+ if (queue >= HALF_QUEUES)
+ return (__raw_readl(&qmgr_regs->statne_h) >>
+ (queue - HALF_QUEUES)) & 0x01;
+ return __qmgr_get_stat1(queue) & QUEUE_STAT1_NEARLY_EMPTY;
+}
+
+/**
+ * qmgr_stat_full() - checks if a hardware queue is full
+ * @queue: queue number
+ *
+ * Returns non-zero value if the queue is full.
+ */
+int qmgr_stat_full(unsigned int queue)
+{
+ if (queue >= HALF_QUEUES)
+ return (__raw_readl(&qmgr_regs->statf_h) >>
+ (queue - HALF_QUEUES)) & 0x01;
+ return __qmgr_get_stat1(queue) & QUEUE_STAT1_FULL;
+}
+
+/**
+ * qmgr_stat_overflow() - checks if a hardware queue experienced overflow
+ * @queue: queue number
+ *
+ * Returns non-zero value if the queue experienced overflow.
+ */
+int qmgr_stat_overflow(unsigned int queue)
+{
+ return __qmgr_get_stat2(queue) & QUEUE_STAT2_OVERFLOW;
+}
+
+void qmgr_set_irq(unsigned int queue, int src,
+ void (*handler)(void *pdev), void *pdev)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&qmgr_lock, flags);
+ if (queue < HALF_QUEUES) {
+ u32 __iomem *reg;
+ int bit;
+ BUG_ON(src > QUEUE_IRQ_SRC_NOT_FULL);
+ reg = &qmgr_regs->irqsrc[queue >> 3]; /* 8 queues per u32 */
+ bit = (queue % 8) * 4; /* 3 bits + 1 reserved bit per queue */
+ __raw_writel((__raw_readl(reg) & ~(7 << bit)) | (src << bit),
+ reg);
+ } else
+ /* IRQ source for queues 32-63 is fixed */
+ BUG_ON(src != QUEUE_IRQ_SRC_NOT_NEARLY_EMPTY);
+
+ irq_handlers[queue] = handler;
+ irq_pdevs[queue] = pdev;
+ spin_unlock_irqrestore(&qmgr_lock, flags);
+}
+
+
+static irqreturn_t qmgr_irq1_a0(int irq, void *pdev)
+{
+ int i, ret = 0;
+ u32 en_bitmap, src, stat;
+
+ /* ACK - it may clear any bits so don't rely on it */
+ __raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[0]);
+
+ en_bitmap = qmgr_regs->irqen[0];
+ while (en_bitmap) {
+ i = __fls(en_bitmap); /* number of the last "low" queue */
+ en_bitmap &= ~BIT(i);
+ src = qmgr_regs->irqsrc[i >> 3];
+ stat = qmgr_regs->stat1[i >> 3];
+ if (src & 4) /* the IRQ condition is inverted */
+ stat = ~stat;
+ if (stat & BIT(src & 3)) {
+ irq_handlers[i](irq_pdevs[i]);
+ ret = IRQ_HANDLED;
+ }
+ }
+ return ret;
+}
+
+
+static irqreturn_t qmgr_irq2_a0(int irq, void *pdev)
+{
+ int i, ret = 0;
+ u32 req_bitmap;
+
+ /* ACK - it may clear any bits so don't rely on it */
+ __raw_writel(0xFFFFFFFF, &qmgr_regs->irqstat[1]);
+
+ req_bitmap = qmgr_regs->irqen[1] & qmgr_regs->statne_h;
+ while (req_bitmap) {
+ i = __fls(req_bitmap); /* number of the last "high" queue */
+ req_bitmap &= ~BIT(i);
+ irq_handlers[HALF_QUEUES + i](irq_pdevs[HALF_QUEUES + i]);
+ ret = IRQ_HANDLED;
+ }
+ return ret;
+}
+
+
+static irqreturn_t qmgr_irq(int irq, void *pdev)
+{
+ int i, half = (irq == qmgr_irq_1 ? 0 : 1);
+ u32 req_bitmap = __raw_readl(&qmgr_regs->irqstat[half]);
+
+ if (!req_bitmap)
+ return 0;
+ __raw_writel(req_bitmap, &qmgr_regs->irqstat[half]); /* ACK */
+
+ while (req_bitmap) {
+ i = __fls(req_bitmap); /* number of the last queue */
+ req_bitmap &= ~BIT(i);
+ i += half * HALF_QUEUES;
+ irq_handlers[i](irq_pdevs[i]);
+ }
+ return IRQ_HANDLED;
+}
+
+
+void qmgr_enable_irq(unsigned int queue)
+{
+ unsigned long flags;
+ int half = queue / 32;
+ u32 mask = 1 << (queue & (HALF_QUEUES - 1));
+
+ spin_lock_irqsave(&qmgr_lock, flags);
+ __raw_writel(__raw_readl(&qmgr_regs->irqen[half]) | mask,
+ &qmgr_regs->irqen[half]);
+ spin_unlock_irqrestore(&qmgr_lock, flags);
+}
+
+void qmgr_disable_irq(unsigned int queue)
+{
+ unsigned long flags;
+ int half = queue / 32;
+ u32 mask = 1 << (queue & (HALF_QUEUES - 1));
+
+ spin_lock_irqsave(&qmgr_lock, flags);
+ __raw_writel(__raw_readl(&qmgr_regs->irqen[half]) & ~mask,
+ &qmgr_regs->irqen[half]);
+ __raw_writel(mask, &qmgr_regs->irqstat[half]); /* clear */
+ 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;
+}
+
+#if DEBUG_QMGR
+int qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */,
+ unsigned int nearly_empty_watermark,
+ unsigned int nearly_full_watermark,
+ const char *desc_format, const char* name)
+#else
+int __qmgr_request_queue(unsigned int queue, unsigned int len /* dwords */,
+ unsigned int nearly_empty_watermark,
+ unsigned int nearly_full_watermark)
+#endif
+{
+ u32 cfg, addr = 0, mask[4]; /* in 16-dwords */
+ int err;
+
+ BUG_ON(queue >= QUEUES);
+
+ 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]);
+#if DEBUG_QMGR
+ snprintf(qmgr_queue_descs[queue], sizeof(qmgr_queue_descs[0]),
+ desc_format, name);
+ printk(KERN_DEBUG "qmgr: requested queue %s(%i) addr = 0x%02X\n",
+ qmgr_queue_descs[queue], queue, addr);
+#endif
+ spin_unlock_irq(&qmgr_lock);
+ 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 >= 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);
+
+#if DEBUG_QMGR
+ printk(KERN_DEBUG "qmgr: releasing queue %s(%i)\n",
+ qmgr_queue_descs[queue], queue);
+ qmgr_queue_descs[queue][0] = '\x0';
+#endif
+
+ while ((addr = qmgr_get_entry(queue)))
+ printk(KERN_ERR "qmgr: released queue %i not empty: 0x%08X\n",
+ queue, addr);
+
+ __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);
+}
+
+static int ixp4xx_qmgr_probe(struct platform_device *pdev)
+{
+ int i, err;
+ irq_handler_t handler1, handler2;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ int irq1, irq2;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+ qmgr_regs = devm_ioremap_resource(dev, res);
+ if (!qmgr_regs)
+ return -ENOMEM;
+
+ irq1 = platform_get_irq(pdev, 0);
+ if (irq1 <= 0)
+ return irq1 ? irq1 : -EINVAL;
+ qmgr_irq_1 = irq1;
+ irq2 = platform_get_irq(pdev, 1);
+ if (irq2 <= 0)
+ return irq2 ? irq2 : -EINVAL;
+ qmgr_irq_2 = irq2;
+
+ /* 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]);
+ }
+
+ __raw_writel(0xFFFFFFFF, &qmgr_regs->statne_h);
+ __raw_writel(0, &qmgr_regs->statf_h);
+
+ for (i = 0; i < QUEUES; i++)
+ __raw_writel(0, &qmgr_regs->sram[i]);
+
+ if (cpu_is_ixp42x_rev_a0()) {
+ handler1 = qmgr_irq1_a0;
+ handler2 = qmgr_irq2_a0;
+ } else
+ handler1 = handler2 = qmgr_irq;
+
+ err = devm_request_irq(dev, irq1, handler1, 0, "IXP4xx Queue Manager",
+ NULL);
+ if (err) {
+ dev_err(dev, "failed to request IRQ%i (%i)\n",
+ irq1, err);
+ return err;
+ }
+
+ err = devm_request_irq(dev, irq2, handler2, 0, "IXP4xx Queue Manager",
+ NULL);
+ if (err) {
+ dev_err(dev, "failed to request IRQ%i (%i)\n",
+ irq2, err);
+ return err;
+ }
+
+ used_sram_bitmap[0] = 0xF; /* 4 first pages reserved for config */
+ spin_lock_init(&qmgr_lock);
+
+ dev_info(dev, "IXP4xx Queue Manager initialized.\n");
+ return 0;
+}
+
+static int ixp4xx_qmgr_remove(struct platform_device *pdev)
+{
+ synchronize_irq(qmgr_irq_1);
+ synchronize_irq(qmgr_irq_2);
+ return 0;
+}
+
+static const struct of_device_id ixp4xx_qmgr_of_match[] = {
+ {
+ .compatible = "intel,ixp4xx-ahb-queue-manager",
+ },
+ {},
+};
+
+static struct platform_driver ixp4xx_qmgr_driver = {
+ .driver = {
+ .name = "ixp4xx-qmgr",
+ .of_match_table = of_match_ptr(ixp4xx_qmgr_of_match),
+ },
+ .probe = ixp4xx_qmgr_probe,
+ .remove = ixp4xx_qmgr_remove,
+};
+module_platform_driver(ixp4xx_qmgr_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Krzysztof Halasa");
+
+EXPORT_SYMBOL(qmgr_put_entry);
+EXPORT_SYMBOL(qmgr_get_entry);
+EXPORT_SYMBOL(qmgr_stat_empty);
+EXPORT_SYMBOL(qmgr_stat_below_low_watermark);
+EXPORT_SYMBOL(qmgr_stat_full);
+EXPORT_SYMBOL(qmgr_stat_overflow);
+EXPORT_SYMBOL(qmgr_set_irq);
+EXPORT_SYMBOL(qmgr_enable_irq);
+EXPORT_SYMBOL(qmgr_disable_irq);
+#if DEBUG_QMGR
+EXPORT_SYMBOL(qmgr_queue_descs);
+EXPORT_SYMBOL(qmgr_request_queue);
+#else
+EXPORT_SYMBOL(__qmgr_request_queue);
+#endif
+EXPORT_SYMBOL(qmgr_release_queue);