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Diffstat (limited to 'arch/mips/pci/msi-octeon.c')
-rw-r--r--arch/mips/pci/msi-octeon.c436
1 files changed, 436 insertions, 0 deletions
diff --git a/arch/mips/pci/msi-octeon.c b/arch/mips/pci/msi-octeon.c
new file mode 100644
index 000000000..cffaaf4aa
--- /dev/null
+++ b/arch/mips/pci/msi-octeon.c
@@ -0,0 +1,436 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2005-2009, 2010 Cavium Networks
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/msi.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-npi-defs.h>
+#include <asm/octeon/cvmx-pci-defs.h>
+#include <asm/octeon/cvmx-npei-defs.h>
+#include <asm/octeon/cvmx-sli-defs.h>
+#include <asm/octeon/cvmx-pexp-defs.h>
+#include <asm/octeon/pci-octeon.h>
+
+/*
+ * Each bit in msi_free_irq_bitmask represents a MSI interrupt that is
+ * in use.
+ */
+static u64 msi_free_irq_bitmask[4];
+
+/*
+ * Each bit in msi_multiple_irq_bitmask tells that the device using
+ * this bit in msi_free_irq_bitmask is also using the next bit. This
+ * is used so we can disable all of the MSI interrupts when a device
+ * uses multiple.
+ */
+static u64 msi_multiple_irq_bitmask[4];
+
+/*
+ * This lock controls updates to msi_free_irq_bitmask and
+ * msi_multiple_irq_bitmask.
+ */
+static DEFINE_SPINLOCK(msi_free_irq_bitmask_lock);
+
+/*
+ * Number of MSI IRQs used. This variable is set up in
+ * the module init time.
+ */
+static int msi_irq_size;
+
+/**
+ * Called when a driver request MSI interrupts instead of the
+ * legacy INT A-D. This routine will allocate multiple interrupts
+ * for MSI devices that support them. A device can override this by
+ * programming the MSI control bits [6:4] before calling
+ * pci_enable_msi().
+ *
+ * @dev: Device requesting MSI interrupts
+ * @desc: MSI descriptor
+ *
+ * Returns 0 on success.
+ */
+int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
+{
+ struct msi_msg msg;
+ u16 control;
+ int configured_private_bits;
+ int request_private_bits;
+ int irq = 0;
+ int irq_step;
+ u64 search_mask;
+ int index;
+
+ /*
+ * Read the MSI config to figure out how many IRQs this device
+ * wants. Most devices only want 1, which will give
+ * configured_private_bits and request_private_bits equal 0.
+ */
+ pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
+
+ /*
+ * If the number of private bits has been configured then use
+ * that value instead of the requested number. This gives the
+ * driver the chance to override the number of interrupts
+ * before calling pci_enable_msi().
+ */
+ configured_private_bits = (control & PCI_MSI_FLAGS_QSIZE) >> 4;
+ if (configured_private_bits == 0) {
+ /* Nothing is configured, so use the hardware requested size */
+ request_private_bits = (control & PCI_MSI_FLAGS_QMASK) >> 1;
+ } else {
+ /*
+ * Use the number of configured bits, assuming the
+ * driver wanted to override the hardware request
+ * value.
+ */
+ request_private_bits = configured_private_bits;
+ }
+
+ /*
+ * The PCI 2.3 spec mandates that there are at most 32
+ * interrupts. If this device asks for more, only give it one.
+ */
+ if (request_private_bits > 5)
+ request_private_bits = 0;
+
+try_only_one:
+ /*
+ * The IRQs have to be aligned on a power of two based on the
+ * number being requested.
+ */
+ irq_step = 1 << request_private_bits;
+
+ /* Mask with one bit for each IRQ */
+ search_mask = (1 << irq_step) - 1;
+
+ /*
+ * We're going to search msi_free_irq_bitmask_lock for zero
+ * bits. This represents an MSI interrupt number that isn't in
+ * use.
+ */
+ spin_lock(&msi_free_irq_bitmask_lock);
+ for (index = 0; index < msi_irq_size/64; index++) {
+ for (irq = 0; irq < 64; irq += irq_step) {
+ if ((msi_free_irq_bitmask[index] & (search_mask << irq)) == 0) {
+ msi_free_irq_bitmask[index] |= search_mask << irq;
+ msi_multiple_irq_bitmask[index] |= (search_mask >> 1) << irq;
+ goto msi_irq_allocated;
+ }
+ }
+ }
+msi_irq_allocated:
+ spin_unlock(&msi_free_irq_bitmask_lock);
+
+ /* Make sure the search for available interrupts didn't fail */
+ if (irq >= 64) {
+ if (request_private_bits) {
+ pr_err("arch_setup_msi_irq: Unable to find %d free interrupts, trying just one",
+ 1 << request_private_bits);
+ request_private_bits = 0;
+ goto try_only_one;
+ } else
+ panic("arch_setup_msi_irq: Unable to find a free MSI interrupt");
+ }
+
+ /* MSI interrupts start at logical IRQ OCTEON_IRQ_MSI_BIT0 */
+ irq += index*64;
+ irq += OCTEON_IRQ_MSI_BIT0;
+
+ switch (octeon_dma_bar_type) {
+ case OCTEON_DMA_BAR_TYPE_SMALL:
+ /* When not using big bar, Bar 0 is based at 128MB */
+ msg.address_lo =
+ ((128ul << 20) + CVMX_PCI_MSI_RCV) & 0xffffffff;
+ msg.address_hi = ((128ul << 20) + CVMX_PCI_MSI_RCV) >> 32;
+ break;
+ case OCTEON_DMA_BAR_TYPE_BIG:
+ /* When using big bar, Bar 0 is based at 0 */
+ msg.address_lo = (0 + CVMX_PCI_MSI_RCV) & 0xffffffff;
+ msg.address_hi = (0 + CVMX_PCI_MSI_RCV) >> 32;
+ break;
+ case OCTEON_DMA_BAR_TYPE_PCIE:
+ /* When using PCIe, Bar 0 is based at 0 */
+ /* FIXME CVMX_NPEI_MSI_RCV* other than 0? */
+ msg.address_lo = (0 + CVMX_NPEI_PCIE_MSI_RCV) & 0xffffffff;
+ msg.address_hi = (0 + CVMX_NPEI_PCIE_MSI_RCV) >> 32;
+ break;
+ case OCTEON_DMA_BAR_TYPE_PCIE2:
+ /* When using PCIe2, Bar 0 is based at 0 */
+ msg.address_lo = (0 + CVMX_SLI_PCIE_MSI_RCV) & 0xffffffff;
+ msg.address_hi = (0 + CVMX_SLI_PCIE_MSI_RCV) >> 32;
+ break;
+ default:
+ panic("arch_setup_msi_irq: Invalid octeon_dma_bar_type");
+ }
+ msg.data = irq - OCTEON_IRQ_MSI_BIT0;
+
+ /* Update the number of IRQs the device has available to it */
+ control &= ~PCI_MSI_FLAGS_QSIZE;
+ control |= request_private_bits << 4;
+ pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control);
+
+ irq_set_msi_desc(irq, desc);
+ pci_write_msi_msg(irq, &msg);
+ return 0;
+}
+
+int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+ struct msi_desc *entry;
+ int ret;
+
+ /*
+ * MSI-X is not supported.
+ */
+ if (type == PCI_CAP_ID_MSIX)
+ return -EINVAL;
+
+ /*
+ * If an architecture wants to support multiple MSI, it needs to
+ * override arch_setup_msi_irqs()
+ */
+ if (type == PCI_CAP_ID_MSI && nvec > 1)
+ return 1;
+
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ ret = arch_setup_msi_irq(dev, entry);
+ if (ret < 0)
+ return ret;
+ if (ret > 0)
+ return -ENOSPC;
+ }
+
+ return 0;
+}
+
+/**
+ * Called when a device no longer needs its MSI interrupts. All
+ * MSI interrupts for the device are freed.
+ *
+ * @irq: The devices first irq number. There may be multple in sequence.
+ */
+void arch_teardown_msi_irq(unsigned int irq)
+{
+ int number_irqs;
+ u64 bitmask;
+ int index = 0;
+ int irq0;
+
+ if ((irq < OCTEON_IRQ_MSI_BIT0)
+ || (irq > msi_irq_size + OCTEON_IRQ_MSI_BIT0))
+ panic("arch_teardown_msi_irq: Attempted to teardown illegal "
+ "MSI interrupt (%d)", irq);
+
+ irq -= OCTEON_IRQ_MSI_BIT0;
+ index = irq / 64;
+ irq0 = irq % 64;
+
+ /*
+ * Count the number of IRQs we need to free by looking at the
+ * msi_multiple_irq_bitmask. Each bit set means that the next
+ * IRQ is also owned by this device.
+ */
+ number_irqs = 0;
+ while ((irq0 + number_irqs < 64) &&
+ (msi_multiple_irq_bitmask[index]
+ & (1ull << (irq0 + number_irqs))))
+ number_irqs++;
+ number_irqs++;
+ /* Mask with one bit for each IRQ */
+ bitmask = (1 << number_irqs) - 1;
+ /* Shift the mask to the correct bit location */
+ bitmask <<= irq0;
+ if ((msi_free_irq_bitmask[index] & bitmask) != bitmask)
+ panic("arch_teardown_msi_irq: Attempted to teardown MSI "
+ "interrupt (%d) not in use", irq);
+
+ /* Checks are done, update the in use bitmask */
+ spin_lock(&msi_free_irq_bitmask_lock);
+ msi_free_irq_bitmask[index] &= ~bitmask;
+ msi_multiple_irq_bitmask[index] &= ~bitmask;
+ spin_unlock(&msi_free_irq_bitmask_lock);
+}
+
+static DEFINE_RAW_SPINLOCK(octeon_irq_msi_lock);
+
+static u64 msi_rcv_reg[4];
+static u64 mis_ena_reg[4];
+
+static void octeon_irq_msi_enable_pcie(struct irq_data *data)
+{
+ u64 en;
+ unsigned long flags;
+ int msi_number = data->irq - OCTEON_IRQ_MSI_BIT0;
+ int irq_index = msi_number >> 6;
+ int irq_bit = msi_number & 0x3f;
+
+ raw_spin_lock_irqsave(&octeon_irq_msi_lock, flags);
+ en = cvmx_read_csr(mis_ena_reg[irq_index]);
+ en |= 1ull << irq_bit;
+ cvmx_write_csr(mis_ena_reg[irq_index], en);
+ cvmx_read_csr(mis_ena_reg[irq_index]);
+ raw_spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
+}
+
+static void octeon_irq_msi_disable_pcie(struct irq_data *data)
+{
+ u64 en;
+ unsigned long flags;
+ int msi_number = data->irq - OCTEON_IRQ_MSI_BIT0;
+ int irq_index = msi_number >> 6;
+ int irq_bit = msi_number & 0x3f;
+
+ raw_spin_lock_irqsave(&octeon_irq_msi_lock, flags);
+ en = cvmx_read_csr(mis_ena_reg[irq_index]);
+ en &= ~(1ull << irq_bit);
+ cvmx_write_csr(mis_ena_reg[irq_index], en);
+ cvmx_read_csr(mis_ena_reg[irq_index]);
+ raw_spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
+}
+
+static struct irq_chip octeon_irq_chip_msi_pcie = {
+ .name = "MSI",
+ .irq_enable = octeon_irq_msi_enable_pcie,
+ .irq_disable = octeon_irq_msi_disable_pcie,
+};
+
+static void octeon_irq_msi_enable_pci(struct irq_data *data)
+{
+ /*
+ * Octeon PCI doesn't have the ability to mask/unmask MSI
+ * interrupts individually. Instead of masking/unmasking them
+ * in groups of 16, we simple assume MSI devices are well
+ * behaved. MSI interrupts are always enable and the ACK is
+ * assumed to be enough
+ */
+}
+
+static void octeon_irq_msi_disable_pci(struct irq_data *data)
+{
+ /* See comment in enable */
+}
+
+static struct irq_chip octeon_irq_chip_msi_pci = {
+ .name = "MSI",
+ .irq_enable = octeon_irq_msi_enable_pci,
+ .irq_disable = octeon_irq_msi_disable_pci,
+};
+
+/*
+ * Called by the interrupt handling code when an MSI interrupt
+ * occurs.
+ */
+static irqreturn_t __octeon_msi_do_interrupt(int index, u64 msi_bits)
+{
+ int irq;
+ int bit;
+
+ bit = fls64(msi_bits);
+ if (bit) {
+ bit--;
+ /* Acknowledge it first. */
+ cvmx_write_csr(msi_rcv_reg[index], 1ull << bit);
+
+ irq = bit + OCTEON_IRQ_MSI_BIT0 + 64 * index;
+ do_IRQ(irq);
+ return IRQ_HANDLED;
+ }
+ return IRQ_NONE;
+}
+
+#define OCTEON_MSI_INT_HANDLER_X(x) \
+static irqreturn_t octeon_msi_interrupt##x(int cpl, void *dev_id) \
+{ \
+ u64 msi_bits = cvmx_read_csr(msi_rcv_reg[(x)]); \
+ return __octeon_msi_do_interrupt((x), msi_bits); \
+}
+
+/*
+ * Create octeon_msi_interrupt{0-3} function body
+ */
+OCTEON_MSI_INT_HANDLER_X(0);
+OCTEON_MSI_INT_HANDLER_X(1);
+OCTEON_MSI_INT_HANDLER_X(2);
+OCTEON_MSI_INT_HANDLER_X(3);
+
+/*
+ * Initializes the MSI interrupt handling code
+ */
+int __init octeon_msi_initialize(void)
+{
+ int irq;
+ struct irq_chip *msi;
+
+ if (octeon_dma_bar_type == OCTEON_DMA_BAR_TYPE_PCIE) {
+ msi_rcv_reg[0] = CVMX_PEXP_NPEI_MSI_RCV0;
+ msi_rcv_reg[1] = CVMX_PEXP_NPEI_MSI_RCV1;
+ msi_rcv_reg[2] = CVMX_PEXP_NPEI_MSI_RCV2;
+ msi_rcv_reg[3] = CVMX_PEXP_NPEI_MSI_RCV3;
+ mis_ena_reg[0] = CVMX_PEXP_NPEI_MSI_ENB0;
+ mis_ena_reg[1] = CVMX_PEXP_NPEI_MSI_ENB1;
+ mis_ena_reg[2] = CVMX_PEXP_NPEI_MSI_ENB2;
+ mis_ena_reg[3] = CVMX_PEXP_NPEI_MSI_ENB3;
+ msi = &octeon_irq_chip_msi_pcie;
+ } else {
+ msi_rcv_reg[0] = CVMX_NPI_NPI_MSI_RCV;
+#define INVALID_GENERATE_ADE 0x8700000000000000ULL;
+ msi_rcv_reg[1] = INVALID_GENERATE_ADE;
+ msi_rcv_reg[2] = INVALID_GENERATE_ADE;
+ msi_rcv_reg[3] = INVALID_GENERATE_ADE;
+ mis_ena_reg[0] = INVALID_GENERATE_ADE;
+ mis_ena_reg[1] = INVALID_GENERATE_ADE;
+ mis_ena_reg[2] = INVALID_GENERATE_ADE;
+ mis_ena_reg[3] = INVALID_GENERATE_ADE;
+ msi = &octeon_irq_chip_msi_pci;
+ }
+
+ for (irq = OCTEON_IRQ_MSI_BIT0; irq <= OCTEON_IRQ_MSI_LAST; irq++)
+ irq_set_chip_and_handler(irq, msi, handle_simple_irq);
+
+ if (octeon_has_feature(OCTEON_FEATURE_PCIE)) {
+ if (request_irq(OCTEON_IRQ_PCI_MSI0, octeon_msi_interrupt0,
+ 0, "MSI[0:63]", octeon_msi_interrupt0))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI0) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI1, octeon_msi_interrupt1,
+ 0, "MSI[64:127]", octeon_msi_interrupt1))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI1) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI2, octeon_msi_interrupt2,
+ 0, "MSI[127:191]", octeon_msi_interrupt2))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI2) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI3, octeon_msi_interrupt3,
+ 0, "MSI[192:255]", octeon_msi_interrupt3))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI3) failed");
+
+ msi_irq_size = 256;
+ } else if (octeon_is_pci_host()) {
+ if (request_irq(OCTEON_IRQ_PCI_MSI0, octeon_msi_interrupt0,
+ 0, "MSI[0:15]", octeon_msi_interrupt0))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI0) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI1, octeon_msi_interrupt0,
+ 0, "MSI[16:31]", octeon_msi_interrupt0))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI1) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI2, octeon_msi_interrupt0,
+ 0, "MSI[32:47]", octeon_msi_interrupt0))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI2) failed");
+
+ if (request_irq(OCTEON_IRQ_PCI_MSI3, octeon_msi_interrupt0,
+ 0, "MSI[48:63]", octeon_msi_interrupt0))
+ panic("request_irq(OCTEON_IRQ_PCI_MSI3) failed");
+ msi_irq_size = 64;
+ }
+ return 0;
+}
+subsys_initcall(octeon_msi_initialize);