Define the vas_win_close() interface which should be used to close a
send or receive windows.
While the hardware configurations required to open send and receive windows
differ, the configuration to close a window is the same for both. So we use
a single interface to close the window.
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/vas.h | 6 +++++
drivers/misc/vas/vas-window.c | 52 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 58 insertions(+)
diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index b6362e9..bda851a 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -75,6 +75,12 @@ struct vas_rx_win_attr {
struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
struct vas_rx_win_attr *attr);
+/*
+ * Close the send or receive window identified by @win. For receive windows
+ * return -EAGAIN if there are active send windows attached to this receive
+ * window.
+ */
+int vas_win_close(struct vas_window *win);
/*
* Get/Set bit fields
diff --git a/drivers/misc/vas/vas-window.c b/drivers/misc/vas/vas-window.c
index a640d59..4b06780 100644
--- a/drivers/misc/vas/vas-window.c
+++ b/drivers/misc/vas/vas-window.c
@@ -711,3 +711,55 @@ struct vas_window *vas_rx_win_open(int vasid, enum
vas_cop_type cop,
vas_release_window_id(&vinst->ida, rxwin->winid);
return ERR_PTR(rc);
}
+
+int vas_win_close(struct vas_window *window)
+{
+ uint64_t val;
+ int cached;
+
+ if (!window)
+ return 0;
+
+ if (!window->tx_win && atomic_read(&window->num_txwins) != 0) {
+ pr_devel("VAS: Attempting to close an active Rx window!\n");
+ WARN_ON_ONCE(1);
+ return -EAGAIN;
+ }
+
+ /* Unpin window from cache and close it */
+ val = 0ULL;
+ val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
+ val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
+ write_hvwc_reg(window, VREG(WINCTL), val);
+
+ /*
+ * See Section 1.11.1 for details on closing window, including
+ * - disable new paste operations
+ * - block till pending requests are completed
+ * - If Rx window, ensure FIFO is empty.
+ */
+
+ /* Cast window context out of the cache */
+retry:
+ val = read_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL));
+ cached = GET_FIELD(val, VAS_WIN_CACHE_STATUS);
+ if (cached) {
+ val = 0ULL;
+ val = SET_FIELD(VAS_CASTOUT_REQ, val, 1);
+ val = SET_FIELD(VAS_PUSH_TO_MEM, val, 0);
+ write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val);
+
+ schedule_timeout(2000);
+ goto retry;
+ }
+
+ /* if send window, drop reference to matching receive window */
+ if (window->tx_win)
+ put_rx_win(window->rxwin);
+
+ vas_release_window_id(&window->vinst->ida, window->winid);
+
+ vas_window_free(window);
+
+ return 0;
+}
--
2.7.4
