diff options
Diffstat (limited to 'drivers/soc/ixp4xx/ixp4xx-qmgr.c')
| -rw-r--r-- | drivers/soc/ixp4xx/ixp4xx-qmgr.c | 487 |
1 files changed, 487 insertions, 0 deletions
diff --git a/drivers/soc/ixp4xx/ixp4xx-qmgr.c b/drivers/soc/ixp4xx/ixp4xx-qmgr.c new file mode 100644 index 000000000..291086bb9 --- /dev/null +++ b/drivers/soc/ixp4xx/ixp4xx-qmgr.c @@ -0,0 +1,487 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Intel IXP4xx Queue Manager driver for Linux + * + * Copyright (C) 2007 Krzysztof Halasa <khc@pm.waw.pl> + */ + +#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> +#include <linux/soc/ixp4xx/cpu.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 = __raw_readl(&qmgr_regs->irqen[0]); + while (en_bitmap) { + i = __fls(en_bitmap); /* number of the last "low" queue */ + en_bitmap &= ~BIT(i); + src = __raw_readl(&qmgr_regs->irqsrc[i >> 3]); + stat = __raw_readl(&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 = __raw_readl(&qmgr_regs->irqen[1]) & + __raw_readl(&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 (IS_ERR(qmgr_regs)) + return PTR_ERR(qmgr_regs); + + 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 = 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); |