[Qemu-devel] [PATCH v2 03/17] ppc/xive: Implement TM_PULL_OS_CTX special command

["Cédric Le Goater" <clg@kaod.org>]

When a vCPU is not dispatched anymore on a HW thread, the Hypervisor
(KVM on Linux) invalidates the OS interrupt context of a vCPU with
this special command. It returns the OS CAM line value and resets the
VO bit.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 hw/intc/xive.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index cf77bdb7d34a..592c0b70f197 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -334,6 +334,17 @@ static void xive_tm_set_os_pending(XiveTCTX *tctx, hwaddr offset,
     xive_tctx_notify(tctx, TM_QW1_OS);
 }
 
+static uint64_t xive_tm_pull_os_ctx(XiveTCTX *tctx, hwaddr offset,
+                                    unsigned size)
+{
+    uint32_t qw1w2_prev = xive_tctx_word2(&tctx->regs[TM_QW1_OS]);
+    uint32_t qw1w2;
+
+    qw1w2 = xive_set_field32(TM_QW1W2_VO, qw1w2_prev, 0);
+    memcpy(&tctx->regs[TM_QW1_OS + TM_WORD2], &qw1w2, 4);
+    return qw1w2;
+}
+
 /*
  * Define a mapping of "special" operations depending on the TIMA page
  * offset and the size of the operation.
@@ -360,6 +371,8 @@ static const XiveTmOp xive_tm_operations[] = {
     /* MMIOs above 2K : special operations with side effects */
     { XIVE_TM_OS_PAGE, TM_SPC_ACK_OS_REG,     2, NULL, xive_tm_ack_os_reg },
     { XIVE_TM_OS_PAGE, TM_SPC_SET_OS_PENDING, 1, xive_tm_set_os_pending, NULL },
+    { XIVE_TM_HV_PAGE, TM_SPC_PULL_OS_CTX,    4, NULL, xive_tm_pull_os_ctx },
+    { XIVE_TM_HV_PAGE, TM_SPC_PULL_OS_CTX,    8, NULL, xive_tm_pull_os_ctx },
     { XIVE_TM_HV_PAGE, TM_SPC_ACK_HV_REG,     2, NULL, xive_tm_ack_hv_reg },
     { XIVE_TM_HV_PAGE, TM_SPC_PULL_POOL_CTX,  4, NULL, xive_tm_pull_pool_ctx },
     { XIVE_TM_HV_PAGE, TM_SPC_PULL_POOL_CTX,  8, NULL, xive_tm_pull_pool_ctx },
@@ -403,7 +416,7 @@ void xive_tctx_tm_write(XiveTCTX *tctx, hwaddr offset, uint64_t value,
     if (offset & 0x800) {
         xto = xive_tm_find_op(offset, size, true);
         if (!xto) {
-            qemu_log_mask(LOG_GUEST_ERROR, "XIVE: invalid write access at TIMA"
+            qemu_log_mask(LOG_GUEST_ERROR, "XIVE: invalid write access at TIMA "
                           "@%"HWADDR_PRIx"\n", offset);
         } else {
             xto->write_handler(tctx, offset, value, size);
-- 
2.21.0