powerpc/powernv/vas: Define vas_rx_win_open() interface

Define the vas_rx_win_open() interface. This interface is intended to
be used by the Nest Accelerator (NX) driver(s) to setup receive
windows for one or more NX engines (which implement compression &
encryption algorithms in the hardware).

Follow-on patches will provide an interface to close the window and to
open a send window that kernel subsystems can use to access the NX
engines.

The interface to open a receive window is expected to be invoked for
each instance of VAS in the system.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 45 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index 7dcf3bded343..18c59c3ade3d 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -50,4 +50,49 @@ enum vas_cop_type {
 	VAS_COP_TYPE_MAX,
 };
 
+/*
+ * Receive window attributes specified by the (in-kernel) owner of window.
+ */
+struct vas_rx_win_attr {
+	void *rx_fifo;
+	int rx_fifo_size;
+	int wcreds_max;
+
+	bool pin_win;
+	bool rej_no_credit;
+	bool tx_wcred_mode;
+	bool rx_wcred_mode;
+	bool tx_win_ord_mode;
+	bool rx_win_ord_mode;
+	bool data_stamp;
+	bool nx_win;
+	bool fault_win;
+	bool user_win;
+	bool notify_disable;
+	bool intr_disable;
+	bool notify_early;
+
+	int lnotify_lpid;
+	int lnotify_pid;
+	int lnotify_tid;
+	u32 pswid;
+
+	int tc_mode;
+};
+
+/*
+ * Helper to initialize receive window attributes to defaults for an
+ * NX window.
+ */
+void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop);
+
+/*
+ * Open a VAS receive window for the instance of VAS identified by @vasid
+ * Use @attr to initialize the attributes of the window.
+ *
+ * Return a handle to the window or ERR_PTR() on error.
+ */
+struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
+				   struct vas_rx_win_attr *attr);
+
 #endif /* __ASM_POWERPC_VAS_H */