pnv/xive2: Handle TIMA access through all ports

The Thread Interrupt Management Area (TIMA) can be accessed through 4
ports, targeted by the address. The base address of a TIMA
is using port 0 and the other ports are 0x80 apart. Using one port or
another can be useful to balance the load on the snoop buses. With
skiboot and linux, we currently use port 0, but as it tends to be
busy, another hypervisor is using port 1 for TIMA access.

The port address bits fall in between the special op indication
bits (the 2 MSBs) and the register offset bits (the 6 LSBs). They are
"don't care" for the hardware when processing a TIMA operation. This
patch filters out those port address bits so that a TIMA operation can
be triggered using any port.

It is also true for indirect access (through the IC BAR) and it's
actually nothing new, it was already the case on P9. Which helps here,
as the TIMA handling code is common between P9 (xive) and P10 (xive2).

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20230601121331.487207-6-fbarrat@linux.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

diff --git a/hw/intc/pnv_xive2.c b/hw/intc/pnv_xive2.c
index 132f82a035422548ca9ea3e4cdde20fb55a1df16..e5a028c1e67581ba2eb659680f251e072bac9659 100644 (file)
--- a/hw/intc/pnv_xive2.c
+++ b/hw/intc/pnv_xive2.c
@@ -1662,6 +1662,8 @@ static void pnv_xive2_tm_write(void *opaque, hwaddr offset,
     bool gen1_tima_os =
         xive->cq_regs[CQ_XIVE_CFG >> 3] & CQ_XIVE_CFG_GEN1_TIMA_OS;
 
+    offset &= TM_ADDRESS_MASK;
+
     /* TODO: should we switch the TM ops table instead ? */
     if (!gen1_tima_os && offset == HV_PUSH_OS_CTX_OFFSET) {
         xive2_tm_push_os_ctx(xptr, tctx, offset, value, size);
@@ -1681,6 +1683,8 @@ static uint64_t pnv_xive2_tm_read(void *opaque, hwaddr offset, unsigned size)
     bool gen1_tima_os =
         xive->cq_regs[CQ_XIVE_CFG >> 3] & CQ_XIVE_CFG_GEN1_TIMA_OS;
 
+    offset &= TM_ADDRESS_MASK;
+
     /* TODO: should we switch the TM ops table instead ? */
     if (!gen1_tima_os && offset == HV_PULL_OS_CTX_OFFSET) {
         return xive2_tm_pull_os_ctx(xptr, tctx, offset, size);

diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index ebe399bc099ade545d91a0c76a0a29ba0057b7d3..5204c14b872b50cfcbb7abb85a6179a3d1dde4ee 100644 (file)
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -500,7 +500,7 @@ static const XiveTmOp xive_tm_operations[] = {
 static const XiveTmOp *xive_tm_find_op(hwaddr offset, unsigned size, bool write)
 {
     uint8_t page_offset = (offset >> TM_SHIFT) & 0x3;
-    uint32_t op_offset = offset & 0xFFF;
+    uint32_t op_offset = offset & TM_ADDRESS_MASK;
     int i;
 
     for (i = 0; i < ARRAY_SIZE(xive_tm_operations); i++) {