From 703992b6cf592645ce22fe00fc3d0b7adcf96987 Mon Sep 17 00:00:00 2001
From: Stefan Lankes <slankes@eonerc.rwth-aachen.de>
Date: Fri, 21 Oct 2016 00:21:01 +0200
Subject: [PATCH] add hbmem support

---
 hermit/arch/x86/kernel/entry.asm |  4 ++++
 hermit/include/hermit/memory.h   | 24 ++++++++++++++++++++++++
 hermit/kernel/main.c             |  4 ++++
 hermit/kernel/syscall.c          | 13 ++++++++++---
 hermit/mm/Makefile               |  2 +-
 hermit/mm/memory.c               |  3 +++
 6 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/hermit/arch/x86/kernel/entry.asm b/hermit/arch/x86/kernel/entry.asm
index 18fc73f9a..a8b38fd62 100644
--- a/hermit/arch/x86/kernel/entry.asm
+++ b/hermit/arch/x86/kernel/entry.asm
@@ -67,6 +67,8 @@ align 4
     global header_size
     global disable_x2apic
     global mb_info
+    global hbmem_base
+    global hbmem_size
     base dq 0
     limit dq 0
     cpu_freq dd 0
@@ -88,6 +90,8 @@ align 4
     disable_x2apic dd 1
     single_kernel dd 1
     mb_info dq 0
+    hbmem_base dq 0
+    hbmem_size dq 0
 
 ; Bootstrap page tables are used during the initialization.
 align 4096
diff --git a/hermit/include/hermit/memory.h b/hermit/include/hermit/memory.h
index 04ab0949e..89ed45f0c 100644
--- a/hermit/include/hermit/memory.h
+++ b/hermit/include/hermit/memory.h
@@ -60,4 +60,28 @@ int put_pages(size_t phyaddr, size_t npages);
  */
 static inline int put_page(size_t phyaddr) { return put_pages(phyaddr, 1); }
 
+/** @brief Request physical hbmem page frames */
+size_t hbmem_get_pages(size_t npages);
+
+/** @brief Get a single hbmem page
+ *
+ * Convenience function: uses hbmem_get_pages(1);
+ */
+static inline size_t hbmem_get_page(void) { return hbmem_get_pages(1); }
+
+/** @brief release physical page frames */
+int hbmem_put_pages(size_t phyaddr, size_t npages);
+
+/** @brief Put a single hbmem page
+ *
+ * Convenience function: uses hbmem_put_pages(1);
+ */
+static inline int hbmem_put_page(size_t phyaddr) { return hbmem_put_pages(phyaddr, 1); }
+
+/** @brief check if high memory bandwidth is available */ 
+int is_hbmem_available(void);
+
+/** @brief Initialize the high bandwidth memory subsystem */
+int hbmemory_init(void);
+
 #endif
diff --git a/hermit/kernel/main.c b/hermit/kernel/main.c
index 4165ed9cb..dfd494e4d 100644
--- a/hermit/kernel/main.c
+++ b/hermit/kernel/main.c
@@ -80,6 +80,8 @@ extern const void percore_start;
 extern const void percore_end0;
 extern const void percore_end;
 extern char __BUILD_DATE;
+extern size_t hbmem_base;
+extern size_t hbmem_size;
 
 /* Page frame counters */
 extern atomic_int64_t total_pages;
@@ -592,6 +594,8 @@ int hermit_main(void)
 	kprintf("Current allocated memory: %zd KiB\n", atomic_int64_read(&total_allocated_pages) * PAGE_SIZE / 1024ULL);
 	kprintf("Current available memory: %zd MiB\n", atomic_int64_read(&total_available_pages) * PAGE_SIZE / (1024ULL*1024ULL));
 	kprintf("Core %d is the boot processor\n", boot_processor);
+	if (hbmem_base)
+		kprintf("Found high bandwidth memory at 0x%zx (size 0x%zx)\n", hbmem_base, hbmem_size);
 
 #if 0
 	print_pci_adapters();
diff --git a/hermit/kernel/syscall.c b/hermit/kernel/syscall.c
index fc5753638..4f110f682 100644
--- a/hermit/kernel/syscall.c
+++ b/hermit/kernel/syscall.c
@@ -496,7 +496,10 @@ int sys_rcce_init(int session_id)
 		goto out;
 	}
 
-	paddr = get_pages(RCCE_MPB_SIZE / PAGE_SIZE);
+	if (is_hbmem_available())
+		paddr = hbmem_get_pages(RCCE_MPB_SIZE / PAGE_SIZE);
+	else
+		paddr = get_pages(RCCE_MPB_SIZE / PAGE_SIZE);
 	if (BUILTIN_EXPECT(!paddr, 0))
 	{
 		err = -ENOMEM;
@@ -592,8 +595,12 @@ int sys_rcce_fini(int session_id)
 		goto out;
 	}
 
-	if (rcce_mpb[i].mpb[isle])
-		put_pages(rcce_mpb[i].mpb[isle], RCCE_MPB_SIZE / PAGE_SIZE);
+	if (rcce_mpb[i].mpb[isle]) {
+		if (is_hbmem_available())
+			hbmem_put_pages(rcce_mpb[i].mpb[isle], RCCE_MPB_SIZE / PAGE_SIZE);
+		else
+			put_pages(rcce_mpb[i].mpb[isle], RCCE_MPB_SIZE / PAGE_SIZE);
+	}
 	rcce_mpb[i].mpb[isle] = 0;
 
 	for(j=0; (j<MAX_ISLE) && !rcce_mpb[i].mpb[j]; j++) {
diff --git a/hermit/mm/Makefile b/hermit/mm/Makefile
index 56c4b8a86..dbcf4aabe 100644
--- a/hermit/mm/Makefile
+++ b/hermit/mm/Makefile
@@ -1,4 +1,4 @@
-C_source := memory.c malloc.c vma.c shm.c
+C_source := memory.c malloc.c vma.c shm.c hbmemory.c
 MODULE := mm
 
 include $(TOPDIR)/Makefile.inc
diff --git a/hermit/mm/memory.c b/hermit/mm/memory.c
index e5c110367..281fddb70 100644
--- a/hermit/mm/memory.c
+++ b/hermit/mm/memory.c
@@ -305,6 +305,9 @@ int memory_init(void)
 
 	kprintf("free list starts at 0x%zx, limit 0x%zx\n", init_list.start, init_list.end);
 
+	// init high bandwidth memory subsystem
+	hbmemory_init();
+
 	ret = vma_init();
 	if (BUILTIN_EXPECT(ret, 0))
 		kprintf("Failed to initialize VMA regions: %d\n", ret);