nova: support write combining

Fixes #1566

repos/base-nova/include/nova/syscall-generic.h

@@ -540,7 +540,8 @@ namespace Nova {
 		                 bool kern_pd = false,
 		                 bool update_guest_pt = false,
 		                 bool translate_map = false,
-		                 bool dma_mem = false)
+		                 bool dma_mem = false,
+		                 bool write_combined = false)
 		{
 			/* transfer items start at the end of the UTCB */
 			items += 1 << 16;
@@ -556,16 +557,19 @@ namespace Nova {
 			/* map from hypervisor or current pd */
 			unsigned h = kern_pd ? (1 << 11) : 0;
 
+			/* map write-combined */
+			unsigned wc = write_combined ? (1 << 10) : 0;
+
 			/* update guest page table */
-			unsigned g = update_guest_pt ? (1 << 10) : 0;
+			unsigned g = update_guest_pt ? (1 << 9) : 0;
 
 			/* mark memory dma able */
-			unsigned d = dma_mem ? (1 << 9) : 0;
+			unsigned d = dma_mem ? (1 << 8) : 0;
 
 			/* set type of delegation, either 'map' or 'translate and map' */
 			unsigned m = translate_map ? 2 : 1;
 
-			item->hotspot = crd.hotspot(sel_hotspot) | g | h | d | m;
+			item->hotspot = crd.hotspot(sel_hotspot) | g | h | wc | d | m;
 			item->crd = crd.value();
 
 			return true;

repos/base-nova/ports/nova.hash

@@ -1 +1 @@
-361b07cc4c3e43610e1bb772932597d45be69c28
+61ea642d86312acd24698976f79d4530132c05a2

repos/base-nova/ports/nova.port

@@ -4,7 +4,7 @@ DOWNLOADS := nova.git
 
 # r9 branch
 URL(nova) := https://github.com/alex-ab/NOVA.git
-REV(nova) := 834519fa28b1f2fc46e3b10746b4838a19470c7a
+REV(nova) := a4a926a749ecdce5ae04d16465aa1872bc626755
 DIR(nova) := src/kernel/nova
 
 PATCHES   := $(wildcard $(REP_DIR)/patches/*.patch)

repos/base-nova/src/core/echo.cc

@@ -44,12 +44,13 @@ static void echo_reply()
 	Nova::mword_t offset = echo()->utcb()->msg[1];
 	bool kern_pd         = echo()->utcb()->msg[2];
 	bool dma_mem         = echo()->utcb()->msg[3];
+	bool write_combined  = echo()->utcb()->msg[4];
 
 	/* reset message transfer descriptor */
 	echo()->utcb()->set_msg_word(0);
 	/* append capability-range as message-transfer item */
 	bool res = echo()->utcb()->append_item(snd_rcv, offset, kern_pd, false,
-	                                       false, dma_mem);
+	                                       false, dma_mem, write_combined);
 
 	/* set return code, 0 means failure */
 	echo()->utcb()->msg[0] = res;

repos/base-nova/src/core/include/ipc_pager.h

@@ -32,7 +32,7 @@ namespace Genode {
 
 			addr_t _dst_addr;
 			addr_t _core_local_addr;
-			bool   _write_combined;
+			Cache_attribute _attr;
 			size_t _size_log2;
 			bool   _rw;
 
@@ -49,8 +49,7 @@ namespace Genode {
 			        bool rw = true)
 			:
 				_dst_addr(dst_addr), _core_local_addr(map_addr),
-				_write_combined(c != CACHED), _size_log2(size_log2),
+				_attr(c), _size_log2(size_log2), _rw(rw)
-				_rw(rw)
 			{ }
 
 			/**
@@ -67,7 +66,8 @@ namespace Genode {
 				                     Nova::Rights(true, _rw, true));
 			}
 
-			bool  write_combined() { return _write_combined; };
+			bool dma() { return _attr != CACHED; };
+			bool write_combined() { return _attr == WRITE_COMBINED; };
 
 			addr_t dst_addr() { return _dst_addr; }
 	};

repos/base-nova/src/core/include/nova_util.h

@@ -64,7 +64,8 @@ inline Genode::addr_t boot_cpu()
  * from the echo EC to the calling EC.
  */
 static int map_local(Nova::Utcb *utcb, Nova::Crd src_crd, Nova::Crd dst_crd,
-                     bool kern_pd = false, bool dma_mem = false)
+                     bool kern_pd = false, bool dma_mem = false,
+                     bool write_combined = false)
 {
 	/* open receive window at current EC */
 	utcb->crd_rcv = dst_crd;
@@ -74,7 +75,8 @@ static int map_local(Nova::Utcb *utcb, Nova::Crd src_crd, Nova::Crd dst_crd,
 	utcb->msg[1] = 0;
 	utcb->msg[2] = kern_pd;
 	utcb->msg[3] = dma_mem;
-	utcb->set_msg_word(4);
+	utcb->msg[4] = write_combined;
+	utcb->set_msg_word(5);
 
 	/* establish the mapping via a portal traversal during reply phase */
 	Nova::uint8_t res = Nova::call(echo()->pt_sel());
@@ -131,7 +133,8 @@ inline int map_local(Nova::Utcb *utcb,
                      Genode::addr_t from_start, Genode::addr_t to_start,
                      Genode::size_t num_pages,
                      Nova::Rights const &permission,
-                     bool kern_pd = false, bool dma_mem = false)
+                     bool kern_pd = false, bool dma_mem = false,
+                     bool write_combined = false)
 {
 	if (verbose_local_map)
 		Genode::printf("::map_local: from %lx to %lx, %zd pages from kernel %u\n",
@@ -173,7 +176,7 @@ inline int map_local(Nova::Utcb *utcb,
 		int const res = map_local(utcb,
 		                          Mem_crd((from_curr >> 12), order - get_page_size_log2(), permission),
 		                          Mem_crd((to_curr   >> 12), order - get_page_size_log2(), permission),
-		                          kern_pd, dma_mem);
+		                          kern_pd, dma_mem, write_combined);
 		if (res) return res;
 
 		/* advance offset by current flexpage size */

repos/base-nova/src/core/ipc_pager.cc

@@ -61,7 +61,7 @@ void Ipc_pager::set_reply_mapping(Mapping m)
 	Nova::Utcb *utcb = (Nova::Utcb *)Thread_base::myself()->utcb();
 	utcb->set_msg_word(0);
 	bool res = utcb->append_item(m.mem_crd(), m.dst_addr(), false, false,
-	                             false, m.write_combined());
+	                             false, m.dma(), m.write_combined());
 	/* one item ever fits on the UTCB */
 	(void)res;
 }