diff options
Diffstat (limited to 'arch/powerpc/sysdev/fsl_msi.c')
| -rw-r--r-- | arch/powerpc/sysdev/fsl_msi.c | 436 | 
1 files changed, 436 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c new file mode 100644 index 00000000000..9d0685babbd --- /dev/null +++ b/arch/powerpc/sysdev/fsl_msi.c @@ -0,0 +1,436 @@ +/* + * Copyright (C) 2007-2008 Freescale Semiconductor, Inc. All rights reserved. + * + * Author: Tony Li <tony.li@freescale.com> + *	   Jason Jin <Jason.jin@freescale.com> + * + * The hwirq alloc and free code reuse from sysdev/mpic_msi.c + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 of the + * License. + * + */ +#include <linux/irq.h> +#include <linux/bootmem.h> +#include <linux/bitmap.h> +#include <linux/msi.h> +#include <linux/pci.h> +#include <linux/of_platform.h> +#include <sysdev/fsl_soc.h> +#include <asm/prom.h> +#include <asm/hw_irq.h> +#include <asm/ppc-pci.h> +#include "fsl_msi.h" + +struct fsl_msi_feature { +	u32 fsl_pic_ip; +	u32 msiir_offset; +}; + +static struct fsl_msi *fsl_msi; + +static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg) +{ +	return in_be32(base + (reg >> 2)); +} + +static inline void fsl_msi_write(u32 __iomem *base, +				unsigned int reg, u32 value) +{ +	out_be32(base + (reg >> 2), value); +} + +/* + * We do not need this actually. The MSIR register has been read once + * in the cascade interrupt. So, this MSI interrupt has been acked +*/ +static void fsl_msi_end_irq(unsigned int virq) +{ +} + +static struct irq_chip fsl_msi_chip = { +	.mask		= mask_msi_irq, +	.unmask		= unmask_msi_irq, +	.ack		= fsl_msi_end_irq, +	.typename	= " FSL-MSI  ", +}; + +static int fsl_msi_host_map(struct irq_host *h, unsigned int virq, +				irq_hw_number_t hw) +{ +	struct irq_chip *chip = &fsl_msi_chip; + +	get_irq_desc(virq)->status |= IRQ_TYPE_EDGE_FALLING; + +	set_irq_chip_and_handler(virq, chip,  handle_edge_irq); + +	return 0; +} + +static struct irq_host_ops fsl_msi_host_ops = { +	.map = fsl_msi_host_map, +}; + +irq_hw_number_t fsl_msi_alloc_hwirqs(struct fsl_msi *msi, int num) +{ +	unsigned long flags; +	int offset, order = get_count_order(num); + +	spin_lock_irqsave(&msi->bitmap_lock, flags); + +	offset = bitmap_find_free_region(msi->fsl_msi_bitmap, +					NR_MSI_IRQS, order); + +	spin_unlock_irqrestore(&msi->bitmap_lock, flags); + +	pr_debug("%s: allocated 0x%x (2^%d) at offset 0x%x\n", +		__func__, num, order, offset); + +	return offset; +} + +void fsl_msi_free_hwirqs(struct fsl_msi *msi, int offset, int num) +{ +	unsigned long flags; +	int order = get_count_order(num); + +	pr_debug("%s: freeing 0x%x (2^%d) at offset 0x%x\n", +		__func__, num, order, offset); + +	spin_lock_irqsave(&msi->bitmap_lock, flags); +	bitmap_release_region(msi->fsl_msi_bitmap, offset, order); +	spin_unlock_irqrestore(&msi->bitmap_lock, flags); +} + +static int fsl_msi_free_dt_hwirqs(struct fsl_msi *msi) +{ +	int i, len; +	const u32 *p; + +	bitmap_allocate_region(msi->fsl_msi_bitmap, 0, +		       get_count_order(NR_MSI_IRQS)); + +	p = of_get_property(msi->of_node, "msi-available-ranges", &len); + +	if (!p) { +		/* No msi-available-ranges property, +		 * All the 256 MSI interrupts can be used +		 */ +		fsl_msi_free_hwirqs(msi, 0, 0x100); +		return 0; +	} + +	if ((len % (2 * sizeof(u32))) != 0) { +		printk(KERN_WARNING "fsl_msi: Malformed msi-available-ranges " +		       "property on %s\n", msi->of_node->full_name); +		return -EINVAL; +	} + +	/* Format is: (<u32 start> <u32 count>)+ */ +	len /= 2 * sizeof(u32); +	for (i = 0; i < len; i++, p += 2) +		fsl_msi_free_hwirqs(msi, *p, *(p + 1)); + +	return 0; +} + +static int fsl_msi_init_allocator(struct fsl_msi *msi_data) +{ +	int rc, size; + +	size = BITS_TO_LONGS(NR_MSI_IRQS) * sizeof(u32); + +	msi_data->fsl_msi_bitmap = kzalloc(size, GFP_KERNEL); + +	if (msi_data->fsl_msi_bitmap == NULL) { +		pr_debug("%s: ENOMEM allocating allocator bitmap!\n", +				__func__); +		return -ENOMEM; +	} + +	rc = fsl_msi_free_dt_hwirqs(msi_data); +	if (rc) +		goto out_free; + +	return 0; +out_free: +	kfree(msi_data->fsl_msi_bitmap); + +	msi_data->fsl_msi_bitmap = NULL; +	return rc; + +} + +static int fsl_msi_check_device(struct pci_dev *pdev, int nvec, int type) +{ +	if (type == PCI_CAP_ID_MSIX) +		pr_debug("fslmsi: MSI-X untested, trying anyway.\n"); + +	return 0; +} + +static void fsl_teardown_msi_irqs(struct pci_dev *pdev) +{ +	struct msi_desc *entry; +	struct fsl_msi *msi_data = fsl_msi; + +	list_for_each_entry(entry, &pdev->msi_list, list) { +		if (entry->irq == NO_IRQ) +			continue; +		set_irq_msi(entry->irq, NULL); +		fsl_msi_free_hwirqs(msi_data, virq_to_hw(entry->irq), 1); +		irq_dispose_mapping(entry->irq); +	} + +	return; +} + +static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq, +				  struct msi_msg *msg) +{ +	struct fsl_msi *msi_data = fsl_msi; + +	msg->address_lo = msi_data->msi_addr_lo; +	msg->address_hi = msi_data->msi_addr_hi; +	msg->data = hwirq; + +	pr_debug("%s: allocated srs: %d, ibs: %d\n", +		__func__, hwirq / IRQS_PER_MSI_REG, hwirq % IRQS_PER_MSI_REG); +} + +static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) +{ +	irq_hw_number_t hwirq; +	int rc; +	unsigned int virq; +	struct msi_desc *entry; +	struct msi_msg msg; +	struct fsl_msi *msi_data = fsl_msi; + +	list_for_each_entry(entry, &pdev->msi_list, list) { +		hwirq = fsl_msi_alloc_hwirqs(msi_data, 1); +		if (hwirq < 0) { +			rc = hwirq; +			pr_debug("%s: fail allocating msi interrupt\n", +					__func__); +			goto out_free; +		} + +		virq = irq_create_mapping(msi_data->irqhost, hwirq); + +		if (virq == NO_IRQ) { +			pr_debug("%s: fail mapping hwirq 0x%lx\n", +					__func__, hwirq); +			fsl_msi_free_hwirqs(msi_data, hwirq, 1); +			rc = -ENOSPC; +			goto out_free; +		} +		set_irq_msi(virq, entry); + +		fsl_compose_msi_msg(pdev, hwirq, &msg); +		write_msi_msg(virq, &msg); +	} +	return 0; + +out_free: +	return rc; +} + +void fsl_msi_cascade(unsigned int irq, struct irq_desc *desc) +{ +	unsigned int cascade_irq; +	struct fsl_msi *msi_data = fsl_msi; +	int msir_index = -1; +	u32 msir_value = 0; +	u32 intr_index; +	u32 have_shift = 0; + +	spin_lock(&desc->lock); +	if ((msi_data->feature &  FSL_PIC_IP_MASK) == FSL_PIC_IP_IPIC) { +		if (desc->chip->mask_ack) +			desc->chip->mask_ack(irq); +		else { +			desc->chip->mask(irq); +			desc->chip->ack(irq); +		} +	} + +	if (unlikely(desc->status & IRQ_INPROGRESS)) +		goto unlock; + +	msir_index = (int)(desc->handler_data); + +	if (msir_index >= NR_MSI_REG) +		cascade_irq = NO_IRQ; + +	desc->status |= IRQ_INPROGRESS; +	switch (fsl_msi->feature & FSL_PIC_IP_MASK) { +	case FSL_PIC_IP_MPIC: +		msir_value = fsl_msi_read(msi_data->msi_regs, +			msir_index * 0x10); +		break; +	case FSL_PIC_IP_IPIC: +		msir_value = fsl_msi_read(msi_data->msi_regs, msir_index * 0x4); +		break; +	} + +	while (msir_value) { +		intr_index = ffs(msir_value) - 1; + +		cascade_irq = irq_linear_revmap(msi_data->irqhost, +				(msir_index * IRQS_PER_MSI_REG + +					intr_index + have_shift)); +		if (cascade_irq != NO_IRQ) +			generic_handle_irq(cascade_irq); +		have_shift += (intr_index + 1); +		msir_value = (msir_value >> (intr_index + 1)); +	} +	desc->status &= ~IRQ_INPROGRESS; + +	switch (msi_data->feature & FSL_PIC_IP_MASK) { +	case FSL_PIC_IP_MPIC: +		desc->chip->eoi(irq); +		break; +	case FSL_PIC_IP_IPIC: +		if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask) +			desc->chip->unmask(irq); +		break; +	} +unlock: +	spin_unlock(&desc->lock); +} + +static int __devinit fsl_of_msi_probe(struct of_device *dev, +				const struct of_device_id *match) +{ +	struct fsl_msi *msi; +	struct resource res; +	int err, i, count; +	int rc; +	int virt_msir; +	const u32 *p; +	struct fsl_msi_feature *tmp_data; + +	printk(KERN_DEBUG "Setting up Freescale MSI support\n"); + +	msi = kzalloc(sizeof(struct fsl_msi), GFP_KERNEL); +	if (!msi) { +		dev_err(&dev->dev, "No memory for MSI structure\n"); +		err = -ENOMEM; +		goto error_out; +	} + +	msi->of_node = of_node_get(dev->node); + +	msi->irqhost = irq_alloc_host(of_node_get(dev->node), +				IRQ_HOST_MAP_LINEAR, +				NR_MSI_IRQS, &fsl_msi_host_ops, 0); +	if (msi->irqhost == NULL) { +		dev_err(&dev->dev, "No memory for MSI irqhost\n"); +		of_node_put(dev->node); +		err = -ENOMEM; +		goto error_out; +	} + +	/* Get the MSI reg base */ +	err = of_address_to_resource(dev->node, 0, &res); +	if (err) { +		dev_err(&dev->dev, "%s resource error!\n", +				dev->node->full_name); +		goto error_out; +	} + +	msi->msi_regs = ioremap(res.start, res.end - res.start + 1); +	if (!msi->msi_regs) { +		dev_err(&dev->dev, "ioremap problem failed\n"); +		goto error_out; +	} + +	tmp_data = (struct fsl_msi_feature *)match->data; + +	msi->feature = tmp_data->fsl_pic_ip; + +	msi->irqhost->host_data = msi; + +	msi->msi_addr_hi = 0x0; +	msi->msi_addr_lo = res.start + tmp_data->msiir_offset; + +	rc = fsl_msi_init_allocator(msi); +	if (rc) { +		dev_err(&dev->dev, "Error allocating MSI bitmap\n"); +		goto error_out; +	} + +	p = of_get_property(dev->node, "interrupts", &count); +	if (!p) { +		dev_err(&dev->dev, "no interrupts property found on %s\n", +				dev->node->full_name); +		err = -ENODEV; +		goto error_out; +	} +	if (count % 8 != 0) { +		dev_err(&dev->dev, "Malformed interrupts property on %s\n", +				dev->node->full_name); +		err = -EINVAL; +		goto error_out; +	} + +	count /= sizeof(u32); +	for (i = 0; i < count / 2; i++) { +		if (i > NR_MSI_REG) +			break; +		virt_msir = irq_of_parse_and_map(dev->node, i); +		if (virt_msir != NO_IRQ) { +			set_irq_data(virt_msir, (void *)i); +			set_irq_chained_handler(virt_msir, fsl_msi_cascade); +		} +	} + +	fsl_msi = msi; + +	WARN_ON(ppc_md.setup_msi_irqs); +	ppc_md.setup_msi_irqs = fsl_setup_msi_irqs; +	ppc_md.teardown_msi_irqs = fsl_teardown_msi_irqs; +	ppc_md.msi_check_device = fsl_msi_check_device; +	return 0; +error_out: +	kfree(msi); +	return err; +} + +static const struct fsl_msi_feature mpic_msi_feature = { +	.fsl_pic_ip = FSL_PIC_IP_MPIC, +	.msiir_offset = 0x140, +}; + +static const struct fsl_msi_feature ipic_msi_feature = { +	.fsl_pic_ip = FSL_PIC_IP_IPIC, +	.msiir_offset = 0x38, +}; + +static const struct of_device_id fsl_of_msi_ids[] = { +	{ +		.compatible = "fsl,mpic-msi", +		.data = (void *)&mpic_msi_feature, +	}, +	{ +		.compatible = "fsl,ipic-msi", +		.data = (void *)&ipic_msi_feature, +	}, +	{} +}; + +static struct of_platform_driver fsl_of_msi_driver = { +	.name = "fsl-msi", +	.match_table = fsl_of_msi_ids, +	.probe = fsl_of_msi_probe, +}; + +static __init int fsl_of_msi_init(void) +{ +	return of_register_platform_driver(&fsl_of_msi_driver); +} + +subsys_initcall(fsl_of_msi_init);  |