[SPARC64]: Consolidate MSI support code.

This also makes us use the MSI queues correctly.

Each MSI queue is serviced by a normal sun4u/sun4v INO interrupt
handler.  This handler runs the MSI queue and dispatches the
virtual interrupts indicated by arriving MSIs in that MSI queue.

All of the common logic is placed in pci_msi.c, with callbacks to
handle the PCI controller specific aspects of the operations.

This common infrastructure will make it much easier to add MSG
support.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 433 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/pci_msi.c b/arch/sparc64/kernel/pci_msi.c
new file mode 100644
index 0000000..0fa33b1
--- /dev/null
+++ b/arch/sparc64/kernel/pci_msi.c
@@ -0,0 +1,433 @@
+/* pci_msi.c: Sparc64 MSI support common layer.
+ *
+ * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
+ */
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+
+#include "pci_impl.h"
+
+static irqreturn_t sparc64_msiq_interrupt(int irq, void *cookie)
+{
+	struct sparc64_msiq_cookie *msiq_cookie = cookie;
+	struct pci_pbm_info *pbm = msiq_cookie->pbm;
+	unsigned long msiqid = msiq_cookie->msiqid;
+	const struct sparc64_msiq_ops *ops;
+	unsigned long orig_head, head;
+	int err;
+
+	ops = pbm->msi_ops;
+
+	err = ops->get_head(pbm, msiqid, &head);
+	if (unlikely(err < 0))
+		goto err_get_head;
+
+	orig_head = head;
+	for (;;) {
+		unsigned long msi;
+
+		err = ops->dequeue_msi(pbm, msiqid, &head, &msi);
+		if (likely(err > 0))
+			__do_IRQ(pbm->msi_irq_table[msi - pbm->msi_first]);
+
+		if (unlikely(err < 0))
+			goto err_dequeue;
+
+		if (err == 0)
+			break;
+	}
+	if (likely(head != orig_head)) {
+		err = ops->set_head(pbm, msiqid, head);
+		if (unlikely(err < 0))
+			goto err_set_head;
+	}
+	return IRQ_HANDLED;
+
+err_get_head:
+	printk(KERN_EMERG "MSI: Get head on msiqid[%lu] gives error %d\n",
+	       msiqid, err);
+	goto err_out;
+
+err_dequeue:
+	printk(KERN_EMERG "MSI: Dequeue head[%lu] from msiqid[%lu] "
+	       "gives error %d\n",
+	       head, msiqid, err);
+	goto err_out;
+
+err_set_head:
+	printk(KERN_EMERG "MSI: Set head[%lu] on msiqid[%lu] "
+	       "gives error %d\n",
+	       head, msiqid, err);
+	goto err_out;
+
+err_out:
+	return IRQ_NONE;
+}
+
+static u32 pick_msiq(struct pci_pbm_info *pbm)
+{
+	static DEFINE_SPINLOCK(rotor_lock);
+	unsigned long flags;
+	u32 ret, rotor;
+
+	spin_lock_irqsave(&rotor_lock, flags);
+
+	rotor = pbm->msiq_rotor;
+	ret = pbm->msiq_first + rotor;
+
+	if (++rotor >= pbm->msiq_num)
+		rotor = 0;
+	pbm->msiq_rotor = rotor;
+
+	spin_unlock_irqrestore(&rotor_lock, flags);
+
+	return ret;
+}
+
+
+static int alloc_msi(struct pci_pbm_info *pbm)
+{
+	int i;
+
+	for (i = 0; i < pbm->msi_num; i++) {
+		if (!test_and_set_bit(i, pbm->msi_bitmap))
+			return i + pbm->msi_first;
+	}
+
+	return -ENOENT;
+}
+
+static void free_msi(struct pci_pbm_info *pbm, int msi_num)
+{
+	msi_num -= pbm->msi_first;
+	clear_bit(msi_num, pbm->msi_bitmap);
+}
+
+static struct irq_chip msi_irq = {
+	.typename	= "PCI-MSI",
+	.mask		= mask_msi_irq,
+	.unmask		= unmask_msi_irq,
+	.enable		= unmask_msi_irq,
+	.disable	= mask_msi_irq,
+	/* XXX affinity XXX */
+};
+
+int sparc64_setup_msi_irq(unsigned int *virt_irq_p,
+			  struct pci_dev *pdev,
+			  struct msi_desc *entry)
+{
+	struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
+	const struct sparc64_msiq_ops *ops = pbm->msi_ops;
+	struct msi_msg msg;
+	int msi, err;
+	u32 msiqid;
+
+	*virt_irq_p = virt_irq_alloc(~0);
+	err = -ENOMEM;
+	if (!*virt_irq_p)
+		goto out_err;
+
+	set_irq_chip(*virt_irq_p, &msi_irq);
+
+	err = alloc_msi(pbm);
+	if (unlikely(err < 0))
+		goto out_virt_irq_free;
+
+	msi = err;
+
+	msiqid = pick_msiq(pbm);
+
+	err = ops->msi_setup(pbm, msiqid, msi,
+			     (entry->msi_attrib.is_64 ? 1 : 0));
+	if (err)
+		goto out_msi_free;
+
+	pbm->msi_irq_table[msi - pbm->msi_first] = *virt_irq_p;
+
+	if (entry->msi_attrib.is_64) {
+		msg.address_hi = pbm->msi64_start >> 32;
+		msg.address_lo = pbm->msi64_start & 0xffffffff;
+	} else {
+		msg.address_hi = 0;
+		msg.address_lo = pbm->msi32_start;
+	}
+	msg.data = msi;
+
+	set_irq_msi(*virt_irq_p, entry);
+	write_msi_msg(*virt_irq_p, &msg);
+
+	return 0;
+
+out_msi_free:
+	free_msi(pbm, msi);
+
+out_virt_irq_free:
+	set_irq_chip(*virt_irq_p, NULL);
+	virt_irq_free(*virt_irq_p);
+	*virt_irq_p = 0;
+
+out_err:
+	return err;
+}
+
+void sparc64_teardown_msi_irq(unsigned int virt_irq,
+			      struct pci_dev *pdev)
+{
+	struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
+	const struct sparc64_msiq_ops *ops = pbm->msi_ops;
+	unsigned int msi_num;
+	int i, err;
+
+	for (i = 0; i < pbm->msi_num; i++) {
+		if (pbm->msi_irq_table[i] == virt_irq)
+			break;
+	}
+	if (i >= pbm->msi_num) {
+		printk(KERN_ERR "%s: teardown: No MSI for irq %u\n",
+		       pbm->name, virt_irq);
+		return;
+	}
+
+	msi_num = pbm->msi_first + i;
+	pbm->msi_irq_table[i] = ~0U;
+
+	err = ops->msi_teardown(pbm, msi_num);
+	if (err) {
+		printk(KERN_ERR "%s: teardown: ops->teardown() on MSI %u, "
+		       "irq %u, gives error %d\n",
+		       pbm->name, msi_num, virt_irq, err);
+		return;
+	}
+
+	free_msi(pbm, msi_num);
+
+	set_irq_chip(virt_irq, NULL);
+	virt_irq_free(virt_irq);
+}
+
+static int msi_bitmap_alloc(struct pci_pbm_info *pbm)
+{
+	unsigned long size, bits_per_ulong;
+
+	bits_per_ulong = sizeof(unsigned long) * 8;
+	size = (pbm->msi_num + (bits_per_ulong - 1)) & ~(bits_per_ulong - 1);
+	size /= 8;
+	BUG_ON(size % sizeof(unsigned long));
+
+	pbm->msi_bitmap = kzalloc(size, GFP_KERNEL);
+	if (!pbm->msi_bitmap)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void msi_bitmap_free(struct pci_pbm_info *pbm)
+{
+	kfree(pbm->msi_bitmap);
+	pbm->msi_bitmap = NULL;
+}
+
+static int msi_table_alloc(struct pci_pbm_info *pbm)
+{
+	int size, i;
+
+	size = pbm->msiq_num * sizeof(struct sparc64_msiq_cookie);
+	pbm->msiq_irq_cookies = kzalloc(size, GFP_KERNEL);
+	if (!pbm->msiq_irq_cookies)
+		return -ENOMEM;
+
+	for (i = 0; i < pbm->msiq_num; i++) {
+		struct sparc64_msiq_cookie *p;
+
+		p = &pbm->msiq_irq_cookies[i];
+		p->pbm = pbm;
+		p->msiqid = pbm->msiq_first + i;
+	}
+
+	size = pbm->msi_num * sizeof(unsigned int);
+	pbm->msi_irq_table = kzalloc(size, GFP_KERNEL);
+	if (!pbm->msi_irq_table) {
+		kfree(pbm->msiq_irq_cookies);
+		pbm->msiq_irq_cookies = NULL;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void msi_table_free(struct pci_pbm_info *pbm)
+{
+	kfree(pbm->msiq_irq_cookies);
+	pbm->msiq_irq_cookies = NULL;
+
+	kfree(pbm->msi_irq_table);
+	pbm->msi_irq_table = NULL;
+}
+
+static int bringup_one_msi_queue(struct pci_pbm_info *pbm,
+				 const struct sparc64_msiq_ops *ops,
+				 unsigned long msiqid,
+				 unsigned long devino)
+{
+	int irq = ops->msiq_build_irq(pbm, msiqid, devino);
+	int err;
+
+	if (irq < 0)
+		return irq;
+
+	err = request_irq(irq, sparc64_msiq_interrupt, 0,
+			  "MSIQ",
+			  &pbm->msiq_irq_cookies[msiqid - pbm->msiq_first]);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int sparc64_bringup_msi_queues(struct pci_pbm_info *pbm,
+				      const struct sparc64_msiq_ops *ops)
+{
+	int i;
+
+	for (i = 0; i < pbm->msiq_num; i++) {
+		unsigned long msiqid = i + pbm->msiq_first;
+		unsigned long devino = i + pbm->msiq_first_devino;
+		int err;
+
+		err = bringup_one_msi_queue(pbm, ops, msiqid, devino);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+void sparc64_pbm_msi_init(struct pci_pbm_info *pbm,
+			  const struct sparc64_msiq_ops *ops)
+{
+	const u32 *val;
+	int len;
+
+	val = of_get_property(pbm->prom_node, "#msi-eqs", &len);
+	if (!val || len != 4)
+		goto no_msi;
+	pbm->msiq_num = *val;
+	if (pbm->msiq_num) {
+		const struct msiq_prop {
+			u32 first_msiq;
+			u32 num_msiq;
+			u32 first_devino;
+		} *mqp;
+		const struct msi_range_prop {
+			u32 first_msi;
+			u32 num_msi;
+		} *mrng;
+		const struct addr_range_prop {
+			u32 msi32_high;
+			u32 msi32_low;
+			u32 msi32_len;
+			u32 msi64_high;
+			u32 msi64_low;
+			u32 msi64_len;
+		} *arng;
+
+		val = of_get_property(pbm->prom_node, "msi-eq-size", &len);
+		if (!val || len != 4)
+			goto no_msi;
+
+		pbm->msiq_ent_count = *val;
+
+		mqp = of_get_property(pbm->prom_node,
+				      "msi-eq-to-devino", &len);
+		if (!mqp)
+			mqp = of_get_property(pbm->prom_node,
+					      "msi-eq-devino", &len);
+		if (!mqp || len != sizeof(struct msiq_prop))
+			goto no_msi;
+
+		pbm->msiq_first = mqp->first_msiq;
+		pbm->msiq_first_devino = mqp->first_devino;
+
+		val = of_get_property(pbm->prom_node, "#msi", &len);
+		if (!val || len != 4)
+			goto no_msi;
+		pbm->msi_num = *val;
+
+		mrng = of_get_property(pbm->prom_node, "msi-ranges", &len);
+		if (!mrng || len != sizeof(struct msi_range_prop))
+			goto no_msi;
+		pbm->msi_first = mrng->first_msi;
+
+		val = of_get_property(pbm->prom_node, "msi-data-mask", &len);
+		if (!val || len != 4)
+			goto no_msi;
+		pbm->msi_data_mask = *val;
+
+		val = of_get_property(pbm->prom_node, "msix-data-width", &len);
+		if (!val || len != 4)
+			goto no_msi;
+		pbm->msix_data_width = *val;
+
+		arng = of_get_property(pbm->prom_node, "msi-address-ranges",
+				       &len);
+		if (!arng || len != sizeof(struct addr_range_prop))
+			goto no_msi;
+		pbm->msi32_start = ((u64)arng->msi32_high << 32) |
+			(u64) arng->msi32_low;
+		pbm->msi64_start = ((u64)arng->msi64_high << 32) |
+			(u64) arng->msi64_low;
+		pbm->msi32_len = arng->msi32_len;
+		pbm->msi64_len = arng->msi64_len;
+
+		if (msi_bitmap_alloc(pbm))
+			goto no_msi;
+
+		if (msi_table_alloc(pbm)) {
+			msi_bitmap_free(pbm);
+			goto no_msi;
+		}
+
+		if (ops->msiq_alloc(pbm)) {
+			msi_table_free(pbm);
+			msi_bitmap_free(pbm);
+			goto no_msi;
+		}
+
+		if (sparc64_bringup_msi_queues(pbm, ops)) {
+			ops->msiq_free(pbm);
+			msi_table_free(pbm);
+			msi_bitmap_free(pbm);
+			goto no_msi;
+		}
+
+		printk(KERN_INFO "%s: MSI Queue first[%u] num[%u] count[%u] "
+		       "devino[0x%x]\n",
+		       pbm->name,
+		       pbm->msiq_first, pbm->msiq_num,
+		       pbm->msiq_ent_count,
+		       pbm->msiq_first_devino);
+		printk(KERN_INFO "%s: MSI first[%u] num[%u] mask[0x%x] "
+		       "width[%u]\n",
+		       pbm->name,
+		       pbm->msi_first, pbm->msi_num, pbm->msi_data_mask,
+		       pbm->msix_data_width);
+		printk(KERN_INFO "%s: MSI addr32[0x%lx:0x%x] "
+		       "addr64[0x%lx:0x%x]\n",
+		       pbm->name,
+		       pbm->msi32_start, pbm->msi32_len,
+		       pbm->msi64_start, pbm->msi64_len);
+		printk(KERN_INFO "%s: MSI queues at RA [%016lx]\n",
+		       pbm->name,
+		       __pa(pbm->msi_queues));
+
+		pbm->msi_ops = ops;
+		pbm->setup_msi_irq = sparc64_setup_msi_irq;
+		pbm->teardown_msi_irq = sparc64_teardown_msi_irq;
+	}
+	return;
+
+no_msi:
+	pbm->msiq_num = 0;
+	printk(KERN_INFO "%s: No MSI support.\n", pbm->name);
+}