efi_loader: Allow boards to implement get_time and reset_system

EFI allows an OS to leverage firmware drivers while the OS is running. In the generic code we so far had to stub those implementations out, because we would need board specific knowledge about MMIO setups for it. However, boards can easily implement those themselves. This patch provides the framework so that a board can implement its own versions of get_time and reset_system which would actually do something useful. While at it we also introduce a simple way for code to reserve MMIO pointers as runtime available. Signed-off-by: Alexander Graf <agraf@suse.de>

efi_loader: Allow boards to implement get_time and reset_system
EFI allows an OS to leverage firmware drivers while the OS is running. In the generic code we so far had to stub those implementations out, because we would need board specific knowledge about MMIO setups for it. However, boards can easily implement those themselves. This patch provides the framework so that a board can implement its own versions of get_time and reset_system which would actually do something useful. While at it we also introduce a simple way for code to reserve MMIO pointers as runtime available. Signed-off-by: Alexander Graf <agraf@suse.de>
Alexander Graf
1 parent 511d0b97ef
Showing 3 changed files with 113 additions and 11 deletions Side-by-side Diff
cmd/bootefi.c
include/efi_loader.h
lib/efi_loader/efi_runtime.c
@@ -206,6 +206,10 @@
 		loaded_image_info.device_handle = nethandle;
 #endif
  
+	/* Initialize EFI runtime services */
+	efi_reset_system_init();
+	efi_get_time_init();
+
 	/* Call our payload! */
 	debug("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
  
@@ -155,11 +155,29 @@
 #define EFI_RUNTIME_DATA __attribute__ ((section ("efi_runtime_data")))
 #define EFI_RUNTIME_TEXT __attribute__ ((section ("efi_runtime_text")))
  
+/* Call this with mmio_ptr as the _pointer_ to a pointer to an MMIO region
+ * to make it available at runtime */
+void efi_add_runtime_mmio(void *mmio_ptr, u64 len);
+
+/* Boards may provide the functions below to implement RTS functionality */
+
+void EFI_RUNTIME_TEXT EFIAPI efi_reset_system(
+			enum efi_reset_type reset_type,
+			efi_status_t reset_status,
+			unsigned long data_size, void *reset_data);
+void efi_reset_system_init(void);
+
+efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_get_time(
+			struct efi_time *time,
+			struct efi_time_cap *capabilities);
+void efi_get_time_init(void);
+
 #else /* defined(EFI_LOADER) && !defined(CONFIG_SPL_BUILD) */
  
 /* Without CONFIG_EFI_LOADER we don't have a runtime section, stub it out */
 #define EFI_RUNTIME_DATA
 #define EFI_RUNTIME_TEXT
+static inline void efi_add_runtime_mmio(void **mmio_ptr, u64 len) { }
  
 /* No loader configured, stub out EFI_ENTRY */
 static inline void efi_restore_gd(void) { }
@@ -16,6 +16,16 @@
 /* For manual relocation support */
 DECLARE_GLOBAL_DATA_PTR;
  
+struct efi_runtime_mmio_list {
+	struct list_head link;
+	void **ptr;
+	u64 paddr;
+	u64 len;
+};
+
+/* This list contains all runtime available mmio regions */
+LIST_HEAD(efi_runtime_mmio);
+
 static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_unimplemented(void);
 static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_device_error(void);
 static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_invalid_parameter(void);
@@ -55,9 +65,10 @@
  * handle a good number of runtime callbacks
  */
  
-static void EFIAPI efi_reset_system(enum efi_reset_type reset_type,
-				    efi_status_t reset_status,
-				    unsigned long data_size, void *reset_data)
+static void EFIAPI efi_reset_system_boottime(
+			enum efi_reset_type reset_type,
+			efi_status_t reset_status,
+			unsigned long data_size, void *reset_data)
 {
 	EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
 		  reset_data);
  
@@ -72,11 +83,12 @@
 		break;
 	}
  
-	EFI_EXIT(EFI_SUCCESS);
+	while (1) { }
 }
  
-static efi_status_t EFIAPI efi_get_time(struct efi_time *time,
-					struct efi_time_cap *capabilities)
+static efi_status_t EFIAPI efi_get_time_boottime(
+			struct efi_time *time,
+			struct efi_time_cap *capabilities)
 {
 #if defined(CONFIG_CMD_DATE) && defined(CONFIG_DM_RTC)
 	struct rtc_time tm;
@@ -107,6 +119,33 @@
 #endif
 }
  
+/* Boards may override the helpers below to implement RTS functionality */
+
+void __weak EFI_RUNTIME_TEXT EFIAPI efi_reset_system(
+			enum efi_reset_type reset_type,
+			efi_status_t reset_status,
+			unsigned long data_size, void *reset_data)
+{
+	/* Nothing we can do */
+	while (1) { }
+}
+
+void __weak efi_reset_system_init(void)
+{
+}
+
+efi_status_t __weak EFI_RUNTIME_TEXT EFIAPI efi_get_time(
+			struct efi_time *time,
+			struct efi_time_cap *capabilities)
+{
+	/* Nothing we can do */
+	return EFI_DEVICE_ERROR;
+}
+
+void __weak efi_get_time_init(void)
+{
+}
+
 struct efi_runtime_detach_list_struct {
 	void *ptr;
 	void *patchto;
@@ -116,7 +155,7 @@
 	{
 		/* do_reset is gone */
 		.ptr = &efi_runtime_services.reset_system,
-		.patchto = NULL,
+		.patchto = efi_reset_system,
 	}, {
 		/* invalidate_*cache_all are gone */
 		.ptr = &efi_runtime_services.set_virtual_address_map,
@@ -124,7 +163,7 @@
 	}, {
 		/* RTC accessors are gone */
 		.ptr = &efi_runtime_services.get_time,
-		.patchto = &efi_device_error,
+		.patchto = &efi_get_time,
 	}, {
 		/* Clean up system table */
 		.ptr = &systab.con_in,
  
  
@@ -233,12 +272,39 @@
 	EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
 		  descriptor_version, virtmap);
  
+	/* Rebind mmio pointers */
 	for (i = 0; i < n; i++) {
+		struct efi_mem_desc *map = (void*)virtmap +
+					   (descriptor_size * i);
+		struct list_head *lhandle;
+		efi_physical_addr_t map_start = map->physical_start;
+		efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
+		efi_physical_addr_t map_end = map_start + map_len;
+
+		/* Adjust all mmio pointers in this region */
+		list_for_each(lhandle, &efi_runtime_mmio) {
+			struct efi_runtime_mmio_list *lmmio;
+
+			lmmio = list_entry(lhandle,
+					   struct efi_runtime_mmio_list,
+					   link);
+			if ((map_start <= lmmio->paddr) &&
+			    (map_end >= lmmio->paddr)) {
+				u64 off = map->virtual_start - map_start;
+				uintptr_t new_addr = lmmio->paddr + off;
+				*lmmio->ptr = (void *)new_addr;
+			}
+		}
+	}
+
+	/* Move the actual runtime code over */
+	for (i = 0; i < n; i++) {
 		struct efi_mem_desc *map;
  
 		map = (void*)virtmap + (descriptor_size * i);
 		if (map->type == EFI_RUNTIME_SERVICES_CODE) {
-			ulong new_offset = map->virtual_start - (runtime_start - gd->relocaddr);
+			ulong new_offset = map->virtual_start -
+					   (runtime_start - gd->relocaddr);
  
 			efi_runtime_relocate(new_offset, map);
 			/* Once we're virtual, we can no longer handle
@@ -251,6 +317,20 @@
 	return EFI_EXIT(EFI_INVALID_PARAMETER);
 }
  
+void efi_add_runtime_mmio(void *mmio_ptr, u64 len)
+{
+	struct efi_runtime_mmio_list *newmmio;
+
+	u64 pages = (len + EFI_PAGE_SIZE - 1) >> EFI_PAGE_SHIFT;
+	efi_add_memory_map(*(uintptr_t *)mmio_ptr, pages, EFI_MMAP_IO, false);
+
+	newmmio = calloc(1, sizeof(*newmmio));
+	newmmio->ptr = mmio_ptr;
+	newmmio->paddr = *(uintptr_t *)mmio_ptr;
+	newmmio->len = len;
+	list_add_tail(&newmmio->link, &efi_runtime_mmio);
+}
+
 /*
  * In the second stage, U-Boot has disappeared. To isolate our runtime code
  * that at this point still exists from the rest, we put it into a special
@@ -292,7 +372,7 @@
 		.revision = EFI_RUNTIME_SERVICES_REVISION,
 		.headersize = sizeof(struct efi_table_hdr),
 	},
-	.get_time = &efi_get_time,
+	.get_time = &efi_get_time_boottime,
 	.set_time = (void *)&efi_device_error,
 	.get_wakeup_time = (void *)&efi_unimplemented,
 	.set_wakeup_time = (void *)&efi_unimplemented,
@@ -302,6 +382,6 @@
 	.get_next_variable = (void *)&efi_device_error,
 	.set_variable = (void *)&efi_device_error,
 	.get_next_high_mono_count = (void *)&efi_device_error,
-	.reset_system = &efi_reset_system,
+	.reset_system = &efi_reset_system_boottime,
 };
...	...	@@ -206,6 +206,10 @@
206	206	loaded_image_info.device_handle = nethandle;
207	207	#endif
208	208
	209	+ /* Initialize EFI runtime services */
	210	+ efi_reset_system_init();
	211	+ efi_get_time_init();
	212	+
209	213	/* Call our payload! */
210	214	debug("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
211	215
...	...	@@ -155,11 +155,29 @@
155	155	#define EFI_RUNTIME_DATA __attribute__ ((section ("efi_runtime_data")))
156	156	#define EFI_RUNTIME_TEXT __attribute__ ((section ("efi_runtime_text")))
157	157
	158	+/* Call this with mmio_ptr as the _pointer_ to a pointer to an MMIO region
	159	+ * to make it available at runtime */
	160	+void efi_add_runtime_mmio(void *mmio_ptr, u64 len);
	161	+
	162	+/* Boards may provide the functions below to implement RTS functionality */
	163	+
	164	+void EFI_RUNTIME_TEXT EFIAPI efi_reset_system(
	165	+ enum efi_reset_type reset_type,
	166	+ efi_status_t reset_status,
	167	+ unsigned long data_size, void *reset_data);
	168	+void efi_reset_system_init(void);
	169	+
	170	+efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_get_time(
	171	+ struct efi_time *time,
	172	+ struct efi_time_cap *capabilities);
	173	+void efi_get_time_init(void);
	174	+
158	175	#else /* defined(EFI_LOADER) && !defined(CONFIG_SPL_BUILD) */
159	176
160	177	/* Without CONFIG_EFI_LOADER we don't have a runtime section, stub it out */
161	178	#define EFI_RUNTIME_DATA
162	179	#define EFI_RUNTIME_TEXT
	180	+static inline void efi_add_runtime_mmio(void **mmio_ptr, u64 len) { }
163	181
164	182	/* No loader configured, stub out EFI_ENTRY */
165	183	static inline void efi_restore_gd(void) { }
...	...	@@ -16,6 +16,16 @@
16	16	/* For manual relocation support */
17	17	DECLARE_GLOBAL_DATA_PTR;
18	18
	19	+struct efi_runtime_mmio_list {
	20	+ struct list_head link;
	21	+ void **ptr;
	22	+ u64 paddr;
	23	+ u64 len;
	24	+};
	25	+
	26	+/* This list contains all runtime available mmio regions */
	27	+LIST_HEAD(efi_runtime_mmio);
	28	+
19	29	static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_unimplemented(void);
20	30	static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_device_error(void);
21	31	static efi_status_t EFI_RUNTIME_TEXT EFIAPI efi_invalid_parameter(void);
...	...	@@ -55,9 +65,10 @@
55	65	* handle a good number of runtime callbacks
56	66	*/
57	67
58		-static void EFIAPI efi_reset_system(enum efi_reset_type reset_type,
59		- efi_status_t reset_status,
60		- unsigned long data_size, void *reset_data)
	68	+static void EFIAPI efi_reset_system_boottime(
	69	+ enum efi_reset_type reset_type,
	70	+ efi_status_t reset_status,
	71	+ unsigned long data_size, void *reset_data)
61	72	{
62	73	EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
63	74	reset_data);
64	75
...	...	@@ -72,11 +83,12 @@
72	83	break;
73	84	}
74	85
75		- EFI_EXIT(EFI_SUCCESS);
	86	+ while (1) { }
76	87	}
77	88
78		-static efi_status_t EFIAPI efi_get_time(struct efi_time *time,
79		- struct efi_time_cap *capabilities)
	89	+static efi_status_t EFIAPI efi_get_time_boottime(
	90	+ struct efi_time *time,
	91	+ struct efi_time_cap *capabilities)
80	92	{
81	93	#if defined(CONFIG_CMD_DATE) && defined(CONFIG_DM_RTC)
82	94	struct rtc_time tm;
...	...	@@ -107,6 +119,33 @@
107	119	#endif
108	120	}
109	121
	122	+/* Boards may override the helpers below to implement RTS functionality */
	123	+
	124	+void __weak EFI_RUNTIME_TEXT EFIAPI efi_reset_system(
	125	+ enum efi_reset_type reset_type,
	126	+ efi_status_t reset_status,
	127	+ unsigned long data_size, void *reset_data)
	128	+{
	129	+ /* Nothing we can do */
	130	+ while (1) { }
	131	+}
	132	+
	133	+void __weak efi_reset_system_init(void)
	134	+{
	135	+}
	136	+
	137	+efi_status_t __weak EFI_RUNTIME_TEXT EFIAPI efi_get_time(
	138	+ struct efi_time *time,
	139	+ struct efi_time_cap *capabilities)
	140	+{
	141	+ /* Nothing we can do */
	142	+ return EFI_DEVICE_ERROR;
	143	+}
	144	+
	145	+void __weak efi_get_time_init(void)
	146	+{
	147	+}
	148	+
110	149	struct efi_runtime_detach_list_struct {
111	150	void *ptr;
112	151	void *patchto;
...	...	@@ -116,7 +155,7 @@
116	155	{
117	156	/* do_reset is gone */
118	157	.ptr = &efi_runtime_services.reset_system,
119		- .patchto = NULL,
	158	+ .patchto = efi_reset_system,
120	159	}, {
121	160	/* invalidate_cache_all are gone /
122	161	.ptr = &efi_runtime_services.set_virtual_address_map,
...	...	@@ -124,7 +163,7 @@
124	163	}, {
125	164	/* RTC accessors are gone */
126	165	.ptr = &efi_runtime_services.get_time,
127		- .patchto = &efi_device_error,
	166	+ .patchto = &efi_get_time,
128	167	}, {
129	168	/* Clean up system table */
130	169	.ptr = &systab.con_in,
131	170
132	171
...	...	@@ -233,12 +272,39 @@
233	272	EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
234	273	descriptor_version, virtmap);
235	274
	275	+ /* Rebind mmio pointers */
236	276	for (i = 0; i < n; i++) {
	277	+ struct efi_mem_desc map = (void)virtmap +
	278	+ (descriptor_size * i);
	279	+ struct list_head *lhandle;
	280	+ efi_physical_addr_t map_start = map->physical_start;
	281	+ efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
	282	+ efi_physical_addr_t map_end = map_start + map_len;
	283	+
	284	+ /* Adjust all mmio pointers in this region */
	285	+ list_for_each(lhandle, &efi_runtime_mmio) {
	286	+ struct efi_runtime_mmio_list *lmmio;
	287	+
	288	+ lmmio = list_entry(lhandle,
	289	+ struct efi_runtime_mmio_list,
	290	+ link);
	291	+ if ((map_start <= lmmio->paddr) &&
	292	+ (map_end >= lmmio->paddr)) {
	293	+ u64 off = map->virtual_start - map_start;
	294	+ uintptr_t new_addr = lmmio->paddr + off;
	295	+ lmmio->ptr = (void )new_addr;
	296	+ }
	297	+ }
	298	+ }
	299	+
	300	+ /* Move the actual runtime code over */
	301	+ for (i = 0; i < n; i++) {
237	302	struct efi_mem_desc *map;
238	303
239	304	map = (void)virtmap + (descriptor_size i);
240	305	if (map->type == EFI_RUNTIME_SERVICES_CODE) {
241		- ulong new_offset = map->virtual_start - (runtime_start - gd->relocaddr);
	306	+ ulong new_offset = map->virtual_start -
	307	+ (runtime_start - gd->relocaddr);
242	308
243	309	efi_runtime_relocate(new_offset, map);
244	310	/* Once we're virtual, we can no longer handle
...	...	@@ -251,6 +317,20 @@
251	317	return EFI_EXIT(EFI_INVALID_PARAMETER);
252	318	}
253	319
	320	+void efi_add_runtime_mmio(void *mmio_ptr, u64 len)
	321	+{
	322	+ struct efi_runtime_mmio_list *newmmio;
	323	+
	324	+ u64 pages = (len + EFI_PAGE_SIZE - 1) >> EFI_PAGE_SHIFT;
	325	+ efi_add_memory_map((uintptr_t )mmio_ptr, pages, EFI_MMAP_IO, false);
	326	+
	327	+ newmmio = calloc(1, sizeof(*newmmio));
	328	+ newmmio->ptr = mmio_ptr;
	329	+ newmmio->paddr = (uintptr_t )mmio_ptr;
	330	+ newmmio->len = len;
	331	+ list_add_tail(&newmmio->link, &efi_runtime_mmio);
	332	+}
	333	+
254	334	/*
255	335	* In the second stage, U-Boot has disappeared. To isolate our runtime code
256	336	* that at this point still exists from the rest, we put it into a special
...	...	@@ -292,7 +372,7 @@
292	372	.revision = EFI_RUNTIME_SERVICES_REVISION,
293	373	.headersize = sizeof(struct efi_table_hdr),
294	374	},
295		- .get_time = &efi_get_time,
	375	+ .get_time = &efi_get_time_boottime,
296	376	.set_time = (void *)&efi_device_error,
297	377	.get_wakeup_time = (void *)&efi_unimplemented,
298	378	.set_wakeup_time = (void *)&efi_unimplemented,
...	...	@@ -302,6 +382,6 @@
302	382	.get_next_variable = (void *)&efi_device_error,
303	383	.set_variable = (void *)&efi_device_error,
304	384	.get_next_high_mono_count = (void *)&efi_device_error,
305		- .reset_system = &efi_reset_system,
	385	+ .reset_system = &efi_reset_system_boottime,
306	386	};