[SPARC64]: Add PCI MSI support on Niagara.

This is kind of hokey, we could use the hardware provided facilities
much better.

MSIs are assosciated with MSI Queues.  MSI Queues generate interrupts
when any MSI assosciated with it is signalled.  This suggests a
two-tiered IRQ dispatch scheme:

	MSI Queue interrupt --> queue interrupt handler
		MSI dispatch --> driver interrupt handler

But we just get one-level under Linux currently.  What I'd like to do
is possibly stick the IRQ actions into a per-MSI-Queue data structure,
and dispatch them form there, but the generic IRQ layer doesn't
provide a way to do that right now.

So, the current kludge is to "ACK" the interrupt by processing the
MSI Queue data structures and ACK'ing them, then we run the actual
handler like normal.

We are wasting a lot of useful information, for example the MSI data
and address are provided with ever MSI, as well as a system tick if
available.  If we could pass this into the IRQ handler it could help
with certain things, in particular for PCI-Express error messages.

The MSI entries on sparc64 also tell you exactly which bus/device/fn
sent the MSI, which would be great for error handling when no
registered IRQ handler can service the interrupt.

We override the disable/enable IRQ chip methods in sun4v_msi, so we
have to call {mask,unmask}_msi_irq() directly from there.  This is
another ugly wart.

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

1 files changed, 266 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/pci_sun4v_asm.S b/arch/sparc64/kernel/pci_sun4v_asm.S
index 6604fdbf746c..ecb81f389b06 100644
--- a/arch/sparc64/kernel/pci_sun4v_asm.S
+++ b/arch/sparc64/kernel/pci_sun4v_asm.S
@@ -93,3 +93,269 @@ pci_sun4v_config_put:
          mov    -1, %o1
 1:      retl
          mov    %o1, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: msiq phys address
+         * %o3: num entries
+         *
+         * returns %o0: status
+         *
+         * status will be zero if the operation completed
+         * successfully, else -1 if not
+         */
+        .globl  pci_sun4v_msiq_conf
+pci_sun4v_msiq_conf:
+        mov     HV_FAST_PCI_MSIQ_CONF, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: &msiq_phys_addr
+         * %o3: &msiq_num_entries
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_info
+pci_sun4v_msiq_info:
+        mov     %o2, %o4
+        mov     HV_FAST_PCI_MSIQ_INFO, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o4]
+        stx     %o2, [%o3]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: &valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_getvalid
+pci_sun4v_msiq_getvalid:
+        mov     HV_FAST_PCI_MSIQ_GETVALID, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_setvalid
+pci_sun4v_msiq_setvalid:
+        mov     HV_FAST_PCI_MSIQ_SETVALID, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: &state
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_getstate
+pci_sun4v_msiq_getstate:
+        mov     HV_FAST_PCI_MSIQ_GETSTATE, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: state
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_setstate
+pci_sun4v_msiq_setstate:
+        mov     HV_FAST_PCI_MSIQ_SETSTATE, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: &head
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_gethead
+pci_sun4v_msiq_gethead:
+        mov     HV_FAST_PCI_MSIQ_GETHEAD, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: head
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_sethead
+pci_sun4v_msiq_sethead:
+        mov     HV_FAST_PCI_MSIQ_SETHEAD, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msiqid
+         * %o2: &tail
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msiq_gettail
+pci_sun4v_msiq_gettail:
+        mov     HV_FAST_PCI_MSIQ_GETTAIL, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: &valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_getvalid
+pci_sun4v_msi_getvalid:
+        mov     HV_FAST_PCI_MSI_GETVALID, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_setvalid
+pci_sun4v_msi_setvalid:
+        mov     HV_FAST_PCI_MSI_SETVALID, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: &msiq
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_getmsiq
+pci_sun4v_msi_getmsiq:
+        mov     HV_FAST_PCI_MSI_GETMSIQ, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: msitype
+         * %o3: msiq
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_setmsiq
+pci_sun4v_msi_setmsiq:
+        mov     HV_FAST_PCI_MSI_SETMSIQ, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: &state
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_getstate
+pci_sun4v_msi_getstate:
+        mov     HV_FAST_PCI_MSI_GETSTATE, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: state
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msi_setstate
+pci_sun4v_msi_setstate:
+        mov     HV_FAST_PCI_MSI_SETSTATE, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: &msiq
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msg_getmsiq
+pci_sun4v_msg_getmsiq:
+        mov     HV_FAST_PCI_MSG_GETMSIQ, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: msiq
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msg_setmsiq
+pci_sun4v_msg_setmsiq:
+        mov     HV_FAST_PCI_MSG_SETMSIQ, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: &valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msg_getvalid
+pci_sun4v_msg_getvalid:
+        mov     HV_FAST_PCI_MSG_GETVALID, %o5
+        ta      HV_FAST_TRAP
+        stx     %o1, [%o2]
+        retl
+         mov    %o0, %o0
+
+        /* %o0: devhandle
+         * %o1: msinum
+         * %o2: valid
+         *
+         * returns %o0: status
+         */
+        .globl  pci_sun4v_msg_setvalid
+pci_sun4v_msg_setvalid:
+        mov     HV_FAST_PCI_MSG_SETVALID, %o5
+        ta      HV_FAST_TRAP
+        retl
+         mov    %o0, %o0
+