MIPS: Octeon: Move MSI code out of octeon-irq.c.

Put all the MSI code in one place (msi-octeon.c).  This simplifies
octeon-irq.c and gets rid of some ugly #ifdefs

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1484/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 88 insertions, 2 deletions

diff --git a/arch/mips/pci/msi-octeon.c b/arch/mips/pci/msi-octeon.c
index 03742e647657..1e31526f0e53 100644
--- a/arch/mips/pci/msi-octeon.c
+++ b/arch/mips/pci/msi-octeon.c
@@ -249,12 +249,99 @@ static irqreturn_t octeon_msi_interrupt(int cpl, void *dev_id)
         return IRQ_NONE;
 }
 
+static DEFINE_RAW_SPINLOCK(octeon_irq_msi_lock);
+
+static void octeon_irq_msi_ack(unsigned int irq)
+{
+        if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
+                /* These chips have PCI */
+                cvmx_write_csr(CVMX_NPI_NPI_MSI_RCV,
+                               1ull << (irq - OCTEON_IRQ_MSI_BIT0));
+        } else {
+                /*
+                 * These chips have PCIe. Thankfully the ACK doesn't
+                 * need any locking.
+                 */
+                cvmx_write_csr(CVMX_PEXP_NPEI_MSI_RCV0,
+                               1ull << (irq - OCTEON_IRQ_MSI_BIT0));
+        }
+}
+
+static void octeon_irq_msi_eoi(unsigned int irq)
+{
+        /* Nothing needed */
+}
+
+static void octeon_irq_msi_enable(unsigned int irq)
+{
+        if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
+                /*
+                 * 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.
+                 */
+        } else {
+                /* These chips have PCIe.  Note that we only support
+                 * the first 64 MSI interrupts.  Unfortunately all the
+                 * MSI enables are in the same register.  We use
+                 * MSI0's lock to control access to them all.
+                 */
+                uint64_t en;
+                unsigned long flags;
+                raw_spin_lock_irqsave(&octeon_irq_msi_lock, flags);
+                en = cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
+                en |= 1ull << (irq - OCTEON_IRQ_MSI_BIT0);
+                cvmx_write_csr(CVMX_PEXP_NPEI_MSI_ENB0, en);
+                cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
+                raw_spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
+        }
+}
+
+static void octeon_irq_msi_disable(unsigned int irq)
+{
+        if (!octeon_has_feature(OCTEON_FEATURE_PCIE)) {
+                /* See comment in enable */
+        } else {
+                /*
+                 * These chips have PCIe.  Note that we only support
+                 * the first 64 MSI interrupts.  Unfortunately all the
+                 * MSI enables are in the same register.  We use
+                 * MSI0's lock to control access to them all.
+                 */
+                uint64_t en;
+                unsigned long flags;
+                raw_spin_lock_irqsave(&octeon_irq_msi_lock, flags);
+                en = cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
+                en &= ~(1ull << (irq - OCTEON_IRQ_MSI_BIT0));
+                cvmx_write_csr(CVMX_PEXP_NPEI_MSI_ENB0, en);
+                cvmx_read_csr(CVMX_PEXP_NPEI_MSI_ENB0);
+                raw_spin_unlock_irqrestore(&octeon_irq_msi_lock, flags);
+        }
+}
+
+static struct irq_chip octeon_irq_chip_msi = {
+        .name = "MSI",
+        .enable = octeon_irq_msi_enable,
+        .disable = octeon_irq_msi_disable,
+        .ack = octeon_irq_msi_ack,
+        .eoi = octeon_irq_msi_eoi,
+};
 
 /*
  * Initializes the MSI interrupt handling code
  */
-int octeon_msi_initialize(void)
+static int __init octeon_msi_initialize(void)
 {
+        int irq;
+
+        for (irq = OCTEON_IRQ_MSI_BIT0; irq <= OCTEON_IRQ_MSI_BIT63; irq++) {
+                set_irq_chip_and_handler(irq, &octeon_irq_chip_msi,
+                                         handle_percpu_irq);
+        }
+
         if (octeon_has_feature(OCTEON_FEATURE_PCIE)) {
                 if (request_irq(OCTEON_IRQ_PCI_MSI0, octeon_msi_interrupt,
                                 IRQF_SHARED,
@@ -284,5 +371,4 @@ int octeon_msi_initialize(void)
         }
         return 0;
 }
-
 subsys_initcall(octeon_msi_initialize);