[RFC PATCH v2 40/48] lmb: notify of any changes to the LMB memory map

[Sughosh Ganu]

In U-Boot, LMB and EFI are two primary modules who provide memory
allocation and reservation API's. Both these modules operate with the
same regions of memory for allocations. Use the LMB memory map update
event to notify other interested listeners about a change in it's
memory map. This can then be used by the other module to keep track of
available and used memory.

Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
---
Changes since V1:
* Notify addition of memory to the LMB memory map.
* Add a function lmb_notify() to check if notification has to be sent.

 lib/lmb.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 3 deletions(-)

diff --git a/lib/lmb.c b/lib/lmb.c
index d2edb3525a..387ec2ac65 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -8,6 +8,7 @@
 
 #include <alist.h>
 #include <efi_loader.h>
+#include <event.h>
 #include <image.h>
 #include <mapmem.h>
 #include <lmb.h>
@@ -21,12 +22,36 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define MAP_OP_RESERVE		(u8)0x1
+#define MAP_OP_FREE		(u8)0x2
+#define MAP_OP_ADD		(u8)0x3
+
 #define LMB_ALLOC_ANYWHERE	0
 #define LMB_ALIST_INITIAL_SIZE	4
 
 struct alist lmb_free_mem;
 struct alist lmb_used_mem;
 
+extern bool is_addr_in_ram(uintptr_t addr);
+
+static bool lmb_notify(enum lmb_flags flags)
+{
+	return !(flags & LMB_NONOTIFY);
+}
+
+static void lmb_map_update_notify(phys_addr_t addr, phys_size_t size,
+				  u8 op)
+{
+	struct event_lmb_map_update lmb_map = {0};
+
+	lmb_map.base = addr;
+	lmb_map.size = size;
+	lmb_map.op = op;
+
+	if (is_addr_in_ram((uintptr_t)addr))
+		event_notify(EVT_LMB_MAP_UPDATE, &lmb_map, sizeof(lmb_map));
+}
+
 static void lmb_dump_region(struct alist *lmb_rgn_lst, char *name)
 {
 	struct lmb_region *rgn = lmb_rgn_lst->data;
@@ -463,9 +488,17 @@ static long lmb_add_region(struct alist *lmb_rgn_lst, phys_addr_t base,
 /* This routine may be called with relocation disabled. */
 long lmb_add(phys_addr_t base, phys_size_t size)
 {
+	long ret;
 	struct alist *lmb_rgn_lst = &lmb_free_mem;
 
-	return lmb_add_region(lmb_rgn_lst, base, size);
+	ret = lmb_add_region(lmb_rgn_lst, base, size);
+	if (ret)
+		return ret;
+
+	if (CONFIG_IS_ENABLED(MEM_MAP_UPDATE_NOTIFY))
+		lmb_map_update_notify(base, size, MAP_OP_ADD);
+
+	return 0;
 }
 
 static long __lmb_free(phys_addr_t base, phys_size_t size)
@@ -521,7 +554,16 @@ static long __lmb_free(phys_addr_t base, phys_size_t size)
 
 long lmb_free(phys_addr_t base, phys_size_t size)
 {
-	return __lmb_free(base, size);
+	long ret;
+
+	ret = __lmb_free(base, size);
+	if (ret < 0)
+		return ret;
+
+	if (CONFIG_IS_ENABLED(MEM_MAP_UPDATE_NOTIFY))
+		lmb_map_update_notify(base, size, MAP_OP_FREE);
+
+	return 0;
 }
 
 long lmb_free_flags(phys_addr_t base, phys_size_t size,
@@ -532,9 +574,17 @@ long lmb_free_flags(phys_addr_t base, phys_size_t size,
 
 long lmb_reserve_flags(phys_addr_t base, phys_size_t size, enum lmb_flags flags)
 {
+	long ret = 0;
 	struct alist *lmb_rgn_lst = &lmb_used_mem;
 
-	return lmb_add_region_flags(lmb_rgn_lst, base, size, flags);
+	ret = lmb_add_region_flags(lmb_rgn_lst, base, size, flags);
+	if (ret < 0)
+		return -1;
+
+	if (CONFIG_IS_ENABLED(MEM_MAP_UPDATE_NOTIFY) && lmb_notify(flags))
+		lmb_map_update_notify(base, size, MAP_OP_RESERVE);
+
+	return ret;
 }
 
 long lmb_reserve(phys_addr_t base, phys_size_t size)
@@ -596,6 +646,11 @@ static phys_addr_t __lmb_alloc_base(phys_size_t size, ulong align,
 				if (lmb_add_region_flags(&lmb_used_mem, base,
 						   size, flags) < 0)
 					return 0;
+
+				if (CONFIG_IS_ENABLED(MEM_MAP_UPDATE_NOTIFY) &&
+				    lmb_notify(flags))
+					lmb_map_update_notify(base, size,
+							      MAP_OP_RESERVE);
 				return base;
 			}
 
-- 
2.34.1