powerpc/vas: Add platform specific user window operations

PowerNV uses registers to open/close VAS windows, and getting the
paste address. Whereas the hypervisor calls are used on PowerVM.

This patch adds the platform specific user space window operations
and register with the common VAS user space interface.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f85091f4ace67f951ac04d60394d67b21e2f5d3c.camel@linux.ibm.com

1 files changed, 44 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 41712b4b268e..26440da4fc6a 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -16,6 +16,7 @@
 #include <linux/mmu_context.h>
 #include <asm/switch_to.h>
 #include <asm/ppc-opcode.h>
+#include <asm/vas.h>
 #include "vas.h"
 #include "copy-paste.h"
 
@@ -1443,6 +1444,48 @@ struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
 	return window;
 }
 
+static struct vas_window *vas_user_win_open(int vas_id, u64 flags,
+				enum vas_cop_type cop_type)
+{
+	struct vas_tx_win_attr txattr = {};
+
+	vas_init_tx_win_attr(&txattr, cop_type);
+
+	txattr.lpid = mfspr(SPRN_LPID);
+	txattr.pidr = mfspr(SPRN_PID);
+	txattr.user_win = true;
+	txattr.rsvd_txbuf_count = false;
+	txattr.pswid = false;
+
+	pr_devel("Pid %d: Opening txwin, PIDR %ld\n", txattr.pidr,
+				mfspr(SPRN_PID));
+
+	return vas_tx_win_open(vas_id, cop_type, &txattr);
+}
+
+static u64 vas_user_win_paste_addr(struct vas_window *win)
+{
+	u64 paste_addr;
+
+	vas_win_paste_addr(win, &paste_addr, NULL);
+
+	return paste_addr;
+}
+
+static int vas_user_win_close(struct vas_window *txwin)
+{
+
+	vas_win_close(txwin);
+
+	return 0;
+}
+
+static const struct vas_user_win_ops vops =  {
+	.open_win	=	vas_user_win_open,
+	.paste_addr	=	vas_user_win_paste_addr,
+	.close_win	=	vas_user_win_close,
+};
+
 /*
  * Supporting only nx-gzip coprocessor type now, but this API code
  * extended to other coprocessor types later.
@@ -1451,7 +1494,7 @@ int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
 			     const char *name)
 {
 
-	return vas_register_coproc_api(mod, cop_type, name);
+	return vas_register_coproc_api(mod, cop_type, name, &vops);
 }
 EXPORT_SYMBOL_GPL(vas_register_api_powernv);