diff --git a/dummyflasher.c b/dummyflasher.c
index e2ec036..cc15b00 100644
--- a/dummyflasher.c
+++ b/dummyflasher.c
@@ -412,10 +412,10 @@
 	return 0;
 }
 
-void *dummy_map(const char *descr, unsigned long phys_addr, size_t len)
+void *dummy_map(const char *descr, uintptr_t phys_addr, size_t len)
 {
-	msg_pspew("%s: Mapping %s, 0x%lx bytes at 0x%08lx\n",
-		  __func__, descr, (unsigned long)len, phys_addr);
+	msg_pspew("%s: Mapping %s, 0x%lx bytes at 0x%*" PRIxPTR "\n",
+		  __func__, descr, (unsigned long)len, PRIxPTR_WIDTH, phys_addr);
 	return (void *)phys_addr;
 }
 
diff --git a/flash.h b/flash.h
index 9e787c0..cba7bd8 100644
--- a/flash.h
+++ b/flash.h
@@ -43,10 +43,10 @@
 
 /* TODO: check using code for correct usage of types */
 typedef uintptr_t chipaddr;
+#define PRIxPTR_WIDTH ((int)(sizeof(uintptr_t)*2))
 
 int register_shutdown(int (*function) (void *data), void *data);
-void *programmer_map_flash_region(const char *descr, unsigned long phys_addr,
-				  size_t len);
+void *programmer_map_flash_region(const char *descr, uintptr_t phys_addr, size_t len);
 void programmer_unmap_flash_region(void *virt_addr, size_t len);
 void programmer_delay(int usecs);
 
diff --git a/flashrom.c b/flashrom.c
index b9c0395..b05faf3 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -417,8 +417,7 @@
 	return ret;
 }
 
-void *programmer_map_flash_region(const char *descr, unsigned long phys_addr,
-				  size_t len)
+void *programmer_map_flash_region(const char *descr, uintptr_t phys_addr, size_t len)
 {
 	return programmer_table[programmer].map_flash_region(descr,
 							     phys_addr, len);
diff --git a/physmap.c b/physmap.c
index 6e3d646..5e22883 100644
--- a/physmap.c
+++ b/physmap.c
@@ -42,7 +42,7 @@
 
 static void *realmem_map;
 
-static void *map_first_meg(unsigned long phys_addr, size_t len)
+static void *map_first_meg(uintptr_t phys_addr, size_t len)
 {
 	if (realmem_map)
 		return realmem_map + phys_addr;
@@ -61,7 +61,7 @@
 	return realmem_map + phys_addr;
 }
 
-static void *sys_physmap(unsigned long phys_addr, size_t len)
+static void *sys_physmap(uintptr_t phys_addr, size_t len)
 {
 	int ret;
 	__dpmi_meminfo mi;
@@ -109,7 +109,7 @@
 
 #define MEM_DEV ""
 
-void *sys_physmap(unsigned long phys_addr, size_t len)
+void *sys_physmap(uintptr_t phys_addr, size_t len)
 {
 	return (void *)phys_to_virt(phys_addr);
 }
@@ -124,7 +124,7 @@
 
 #define MEM_DEV "DirectHW"
 
-static void *sys_physmap(unsigned long phys_addr, size_t len)
+static void *sys_physmap(uintptr_t phys_addr, size_t len)
 {
 	/* The short form of ?: is a GNU extension.
 	 * FIXME: map_physical returns NULL both for errors and for success
@@ -156,7 +156,7 @@
 static int fd_mem_cached = -1;
 
 /* For MMIO access. Must be uncached, doesn't make sense to restrict to ro. */
-static void *sys_physmap_rw_uncached(unsigned long phys_addr, size_t len)
+static void *sys_physmap_rw_uncached(uintptr_t phys_addr, size_t len)
 {
 	void *virt_addr;
 
@@ -176,7 +176,7 @@
 /* For reading DMI/coreboot/whatever tables. We should never write, and we
  * do not care about caching.
  */
-static void *sys_physmap_ro_cached(unsigned long phys_addr, size_t len)
+static void *sys_physmap_ro_cached(uintptr_t phys_addr, size_t len)
 {
 	void *virt_addr;
 
@@ -209,25 +209,24 @@
 #define PHYSMAP_RW	0
 #define PHYSMAP_RO	1
 
-static void *physmap_common(const char *descr, unsigned long phys_addr,
+static void *physmap_common(const char *descr, uintptr_t phys_addr,
 			    size_t len, int mayfail, int readonly)
 {
 	void *virt_addr;
 
 	if (len == 0) {
-		msg_pspew("Not mapping %s, zero size at 0x%08lx.\n",
-			  descr, phys_addr);
+		msg_pspew("Not mapping %s, zero size at 0x%0*" PRIxPTR ".\n", descr, PRIxPTR_WIDTH, phys_addr);
 		return ERROR_PTR;
 	}
 
 	if ((getpagesize() - 1) & len) {
-		msg_perr("Mapping %s at 0x%08lx, unaligned size 0x%lx.\n",
-			 descr, phys_addr, (unsigned long)len);
+		msg_perr("Mapping %s at 0x%0*" PRIxPTR ", unaligned size 0x%lx.\n",
+			 descr, PRIxPTR_WIDTH, phys_addr, (unsigned long)len);
 	}
 
 	if ((getpagesize() - 1) & phys_addr) {
-		msg_perr("Mapping %s, 0x%lx bytes at unaligned 0x%08lx.\n",
-			 descr, (unsigned long)len, phys_addr);
+		msg_perr("Mapping %s, 0x%lx bytes at unaligned 0x%0*" PRIxPTR ".\n",
+			 descr, (unsigned long)len, PRIxPTR_WIDTH, phys_addr);
 	}
 
 	if (readonly)
@@ -238,8 +237,8 @@
 	if (ERROR_PTR == virt_addr) {
 		if (NULL == descr)
 			descr = "memory";
-		msg_perr("Error accessing %s, 0x%lx bytes at 0x%08lx\n", descr,
-			 (unsigned long)len, phys_addr);
+		msg_perr("Error accessing %s, 0x%lx bytes at 0x%0*" PRIxPTR "\n",
+			 descr, (unsigned long)len, PRIxPTR_WIDTH, phys_addr);
 		msg_perr(MEM_DEV " mmap failed: %s\n", strerror(errno));
 #ifdef __linux__
 		if (EINVAL == errno) {
@@ -261,13 +260,13 @@
 	return virt_addr;
 }
 
-void *physmap(const char *descr, unsigned long phys_addr, size_t len)
+void *physmap(const char *descr, uintptr_t phys_addr, size_t len)
 {
 	return physmap_common(descr, phys_addr, len, PHYSMAP_NOFAIL,
 			      PHYSMAP_RW);
 }
 
-void *physmap_try_ro(const char *descr, unsigned long phys_addr, size_t len)
+void *physmap_try_ro(const char *descr, uintptr_t phys_addr, size_t len)
 {
 	return physmap_common(descr, phys_addr, len, PHYSMAP_MAYFAIL,
 			      PHYSMAP_RO);
diff --git a/programmer.c b/programmer.c
index 3b4def0..bf7dca1 100644
--- a/programmer.c
+++ b/programmer.c
@@ -28,7 +28,7 @@
 }
 
 /* Fallback map() for programmers which don't need special handling */
-void *fallback_map(const char *descr, unsigned long phys_addr, size_t len)
+void *fallback_map(const char *descr, uintptr_t phys_addr, size_t len)
 {
 	/* FIXME: Should return phys_addr. */
 	return NULL;
diff --git a/programmer.h b/programmer.h
index 2ea7b48..db914cb 100644
--- a/programmer.h
+++ b/programmer.h
@@ -117,7 +117,7 @@
 
 	int (*init) (void);
 
-	void *(*map_flash_region) (const char *descr, unsigned long phys_addr, size_t len);
+	void *(*map_flash_region) (const char *descr, uintptr_t phys_addr, size_t len);
 	void (*unmap_flash_region) (void *virt_addr, size_t len);
 
 	void (*delay) (int usecs);
@@ -275,8 +275,8 @@
 #endif
 
 /* physmap.c */
-void *physmap(const char *descr, unsigned long phys_addr, size_t len);
-void *physmap_try_ro(const char *descr, unsigned long phys_addr, size_t len);
+void *physmap(const char *descr, uintptr_t phys_addr, size_t len);
+void *physmap_try_ro(const char *descr, uintptr_t phys_addr, size_t len);
 void physunmap(void *virt_addr, size_t len);
 #if CONFIG_INTERNAL == 1
 int setup_cpu_msr(int cpu);
@@ -359,7 +359,7 @@
 /* dummyflasher.c */
 #if CONFIG_DUMMY == 1
 int dummy_init(void);
-void *dummy_map(const char *descr, unsigned long phys_addr, size_t len);
+void *dummy_map(const char *descr, uintptr_t phys_addr, size_t len);
 void dummy_unmap(void *virt_addr, size_t len);
 #endif
 
@@ -606,7 +606,7 @@
 
 /* programmer.c */
 int noop_shutdown(void);
-void *fallback_map(const char *descr, unsigned long phys_addr, size_t len);
+void *fallback_map(const char *descr, uintptr_t phys_addr, size_t len);
 void fallback_unmap(void *virt_addr, size_t len);
 void noop_chip_writeb(const struct flashctx *flash, uint8_t val, chipaddr addr);
 void fallback_chip_writew(const struct flashctx *flash, uint16_t val, chipaddr addr);