Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux

Pull Exynos platform DT fix from Grant Likely: "Device tree Exynos bug fix for v3.16-rc7 This bug fix has been brewing for a while. I hate sending it to you so late, but I only got confirmation that it solves the problem this past weekend. The diff looks big for a bug fix, but the majority of it is only executed in the Exynos quirk case. Unfortunately it required splitting early_init_dt_scan() in two and adding quirk handling in the middle of it on ARM. Exynos has buggy firmware that puts bad data into the memory node. Commit 1c2f87c22566 ("ARM: Get rid of meminfo") exposed the bug by dropping the artificial upper bound on the number of memory banks that can be added. Exynos fails to boot after that commit. This branch fixes it by splitting the early DT parse function and inserting a fixup hook. Exynos uses the hook to correct the DT before parsing memory regions" * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: arm: Add devicetree fixup machine function of: Add memory limiting function for flattened devicetrees of: Split early_init_dt_scan into two parts

Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux
Pull Exynos platform DT fix from Grant Likely: "Device tree Exynos bug fix for v3.16-rc7 This bug fix has been brewing for a while. I hate sending it to you so late, but I only got confirmation that it solves the problem this past weekend. The diff looks big for a bug fix, but the majority of it is only executed in the Exynos quirk case. Unfortunately it required splitting early_init_dt_scan() in two and adding quirk handling in the middle of it on ARM. Exynos has buggy firmware that puts bad data into the memory node. Commit 1c2f87c22566 ("ARM: Get rid of meminfo") exposed the bug by dropping the artificial upper bound on the number of memory banks that can be added. Exynos fails to boot after that commit. This branch fixes it by splitting the early DT parse function and inserting a fixup hook. Exynos uses the hook to correct the DT before parsing memory regions" * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: arm: Add devicetree fixup machine function of: Add memory limiting function for flattened devicetrees of: Split early_init_dt_scan into two parts
Linus Torvalds
2 parents acba648dca 5a12a597a8
Showing 5 changed files Side-by-side Diff
arch/arm/include/asm/mach/arch.h
arch/arm/kernel/devtree.c
arch/arm/mach-exynos/exynos.c
drivers/of/fdt.c
include/linux/of_fdt.h
@@ -50,6 +50,7 @@
 	struct smp_operations	*smp;		/* SMP operations	*/
 	bool			(*smp_init)(void);
 	void			(*fixup)(struct tag *, char **);
+	void			(*dt_fixup)(void);
 	void			(*init_meminfo)(void);
 	void			(*reserve)(void);/* reserve mem blocks	*/
 	void			(*map_io)(void);/* IO mapping function	*/
@@ -212,7 +212,7 @@
 	mdesc_best = &__mach_desc_GENERIC_DT;
 #endif
  
-	if (!dt_phys || !early_init_dt_scan(phys_to_virt(dt_phys)))
+	if (!dt_phys || !early_init_dt_verify(phys_to_virt(dt_phys)))
 		return NULL;
  
 	mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
@@ -236,6 +236,12 @@
  
 		dump_machine_table(); /* does not return */
 	}
+
+	/* We really don't want to do this, but sometimes firmware provides buggy data */
+	if (mdesc->dt_fixup)
+		mdesc->dt_fixup();
+
+	early_init_dt_scan_nodes();
  
 	/* Change machine number to match the mdesc we're using */
 	__machine_arch_type = mdesc->nr;
@@ -335,6 +335,15 @@
 #endif
 }
  
+static void __init exynos_dt_fixup(void)
+{
+	/*
+	 * Some versions of uboot pass garbage entries in the memory node,
+	 * use the old CONFIG_ARM_NR_BANKS
+	 */
+	of_fdt_limit_memory(8);
+}
+
 DT_MACHINE_START(EXYNOS_DT, "SAMSUNG EXYNOS (Flattened Device Tree)")
 	/* Maintainer: Thomas Abraham <thomas.abraham@linaro.org> */
 	/* Maintainer: Kukjin Kim <kgene.kim@samsung.com> */
@@ -348,5 +357,6 @@
 	.dt_compat	= exynos_dt_compat,
 	.restart	= exynos_restart,
 	.reserve	= exynos_reserve,
+	.dt_fixup	= exynos_dt_fixup,
 MACHINE_END
@@ -26,6 +26,54 @@
 #include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
 #include <asm/page.h>
  
+/*
+ * of_fdt_limit_memory - limit the number of regions in the /memory node
+ * @limit: maximum entries
+ *
+ * Adjust the flattened device tree to have at most 'limit' number of
+ * memory entries in the /memory node. This function may be called
+ * any time after initial_boot_param is set.
+ */
+void of_fdt_limit_memory(int limit)
+{
+	int memory;
+	int len;
+	const void *val;
+	int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
+	int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
+	const uint32_t *addr_prop;
+	const uint32_t *size_prop;
+	int root_offset;
+	int cell_size;
+
+	root_offset = fdt_path_offset(initial_boot_params, "/");
+	if (root_offset < 0)
+		return;
+
+	addr_prop = fdt_getprop(initial_boot_params, root_offset,
+				"#address-cells", NULL);
+	if (addr_prop)
+		nr_address_cells = fdt32_to_cpu(*addr_prop);
+
+	size_prop = fdt_getprop(initial_boot_params, root_offset,
+				"#size-cells", NULL);
+	if (size_prop)
+		nr_size_cells = fdt32_to_cpu(*size_prop);
+
+	cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
+
+	memory = fdt_path_offset(initial_boot_params, "/memory");
+	if (memory > 0) {
+		val = fdt_getprop(initial_boot_params, memory, "reg", &len);
+		if (len > limit*cell_size) {
+			len = limit*cell_size;
+			pr_debug("Limiting number of entries to %d\n", limit);
+			fdt_setprop(initial_boot_params, memory, "reg", val,
+					len);
+		}
+	}
+}
+
 /**
  * of_fdt_is_compatible - Return true if given node from the given blob has
  * compat in its compatible list
@@ -937,7 +985,7 @@
 }
 #endif
  
-bool __init early_init_dt_scan(void *params)
+bool __init early_init_dt_verify(void *params)
 {
 	if (!params)
 		return false;
@@ -951,6 +999,12 @@
 		return false;
 	}
  
+	return true;
+}
+
+
+void __init early_init_dt_scan_nodes(void)
+{
 	/* Retrieve various information from the /chosen node */
 	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
  
  
@@ -959,7 +1013,17 @@
  
 	/* Setup memory, calling early_init_dt_add_memory_arch */
 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
+}
  
+bool __init early_init_dt_scan(void *params)
+{
+	bool status;
+
+	status = early_init_dt_verify(params);
+	if (!status)
+		return false;
+
+	early_init_dt_scan_nodes();
 	return true;
 }
  
@@ -73,6 +73,8 @@
 				   int depth, void *data);
  
 extern bool early_init_dt_scan(void *params);
+extern bool early_init_dt_verify(void *params);
+extern void early_init_dt_scan_nodes(void);
  
 extern const char *of_flat_dt_get_machine_name(void);
 extern const void *of_flat_dt_match_machine(const void *default_match,
@@ -84,6 +86,7 @@
 extern void early_init_devtree(void *);
 extern void early_get_first_memblock_info(void *, phys_addr_t *);
 extern u64 fdt_translate_address(const void *blob, int node_offset);
+extern void of_fdt_limit_memory(int limit);
 #else /* CONFIG_OF_FLATTREE */
 static inline void early_init_fdt_scan_reserved_mem(void) {}
 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
...	...	@@ -50,6 +50,7 @@
50	50	struct smp_operations smp; / SMP operations */
51	51	bool (*smp_init)(void);
52	52	void (fixup)(struct tag , char **);
	53	+ void (*dt_fixup)(void);
53	54	void (*init_meminfo)(void);
54	55	void (reserve)(void);/ reserve mem blocks */
55	56	void (map_io)(void);/ IO mapping function */
...	...	@@ -212,7 +212,7 @@
212	212	mdesc_best = &__mach_desc_GENERIC_DT;
213	213	#endif
214	214
215		- if (!dt_phys \|\| !early_init_dt_scan(phys_to_virt(dt_phys)))
	215	+ if (!dt_phys \|\| !early_init_dt_verify(phys_to_virt(dt_phys)))
216	216	return NULL;
217	217
218	218	mdesc = of_flat_dt_match_machine(mdesc_best, arch_get_next_mach);
...	...	@@ -236,6 +236,12 @@
236	236
237	237	dump_machine_table(); /* does not return */
238	238	}
	239	+
	240	+ /* We really don't want to do this, but sometimes firmware provides buggy data */
	241	+ if (mdesc->dt_fixup)
	242	+ mdesc->dt_fixup();
	243	+
	244	+ early_init_dt_scan_nodes();
239	245
240	246	/* Change machine number to match the mdesc we're using */
241	247	__machine_arch_type = mdesc->nr;
...	...	@@ -335,6 +335,15 @@
335	335	#endif
336	336	}
337	337
	338	+static void __init exynos_dt_fixup(void)
	339	+{
	340	+ /*
	341	+ * Some versions of uboot pass garbage entries in the memory node,
	342	+ * use the old CONFIG_ARM_NR_BANKS
	343	+ */
	344	+ of_fdt_limit_memory(8);
	345	+}
	346	+
338	347	DT_MACHINE_START(EXYNOS_DT, "SAMSUNG EXYNOS (Flattened Device Tree)")
339	348	/* Maintainer: Thomas Abraham <thomas.abraham@linaro.org> */
340	349	/* Maintainer: Kukjin Kim <kgene.kim@samsung.com> */
...	...	@@ -348,5 +357,6 @@
348	357	.dt_compat = exynos_dt_compat,
349	358	.restart = exynos_restart,
350	359	.reserve = exynos_reserve,
	360	+ .dt_fixup = exynos_dt_fixup,
351	361	MACHINE_END
...	...	@@ -26,6 +26,54 @@
26	26	#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
27	27	#include <asm/page.h>
28	28
	29	+/*
	30	+ * of_fdt_limit_memory - limit the number of regions in the /memory node
	31	+ * @limit: maximum entries
	32	+ *
	33	+ * Adjust the flattened device tree to have at most 'limit' number of
	34	+ * memory entries in the /memory node. This function may be called
	35	+ * any time after initial_boot_param is set.
	36	+ */
	37	+void of_fdt_limit_memory(int limit)
	38	+{
	39	+ int memory;
	40	+ int len;
	41	+ const void *val;
	42	+ int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
	43	+ int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
	44	+ const uint32_t *addr_prop;
	45	+ const uint32_t *size_prop;
	46	+ int root_offset;
	47	+ int cell_size;
	48	+
	49	+ root_offset = fdt_path_offset(initial_boot_params, "/");
	50	+ if (root_offset < 0)
	51	+ return;
	52	+
	53	+ addr_prop = fdt_getprop(initial_boot_params, root_offset,
	54	+ "#address-cells", NULL);
	55	+ if (addr_prop)
	56	+ nr_address_cells = fdt32_to_cpu(*addr_prop);
	57	+
	58	+ size_prop = fdt_getprop(initial_boot_params, root_offset,
	59	+ "#size-cells", NULL);
	60	+ if (size_prop)
	61	+ nr_size_cells = fdt32_to_cpu(*size_prop);
	62	+
	63	+ cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
	64	+
	65	+ memory = fdt_path_offset(initial_boot_params, "/memory");
	66	+ if (memory > 0) {
	67	+ val = fdt_getprop(initial_boot_params, memory, "reg", &len);
	68	+ if (len > limit*cell_size) {
	69	+ len = limit*cell_size;
	70	+ pr_debug("Limiting number of entries to %d\n", limit);
	71	+ fdt_setprop(initial_boot_params, memory, "reg", val,
	72	+ len);
	73	+ }
	74	+ }
	75	+}
	76	+
29	77	/**
30	78	* of_fdt_is_compatible - Return true if given node from the given blob has
31	79	* compat in its compatible list
...	...	@@ -937,7 +985,7 @@
937	985	}
938	986	#endif
939	987
940		-bool __init early_init_dt_scan(void *params)
	988	+bool __init early_init_dt_verify(void *params)
941	989	{
942	990	if (!params)
943	991	return false;
...	...	@@ -951,6 +999,12 @@
951	999	return false;
952	1000	}
953	1001
	1002	+ return true;
	1003	+}
	1004	+
	1005	+
	1006	+void __init early_init_dt_scan_nodes(void)
	1007	+{
954	1008	/* Retrieve various information from the /chosen node */
955	1009	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
956	1010
957	1011
...	...	@@ -959,7 +1013,17 @@
959	1013
960	1014	/* Setup memory, calling early_init_dt_add_memory_arch */
961	1015	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
	1016	+}
962	1017
	1018	+bool __init early_init_dt_scan(void *params)
	1019	+{
	1020	+ bool status;
	1021	+
	1022	+ status = early_init_dt_verify(params);
	1023	+ if (!status)
	1024	+ return false;
	1025	+
	1026	+ early_init_dt_scan_nodes();
963	1027	return true;
964	1028	}
965	1029
...	...	@@ -73,6 +73,8 @@
73	73	int depth, void *data);
74	74
75	75	extern bool early_init_dt_scan(void *params);
	76	+extern bool early_init_dt_verify(void *params);
	77	+extern void early_init_dt_scan_nodes(void);
76	78
77	79	extern const char *of_flat_dt_get_machine_name(void);
78	80	extern const void of_flat_dt_match_machine(const void default_match,
...	...	@@ -84,6 +86,7 @@
84	86	extern void early_init_devtree(void *);
85	87	extern void early_get_first_memblock_info(void , phys_addr_t );
86	88	extern u64 fdt_translate_address(const void *blob, int node_offset);
	89	+extern void of_fdt_limit_memory(int limit);
87	90	#else /* CONFIG_OF_FLATTREE */
88	91	static inline void early_init_fdt_scan_reserved_mem(void) {}
89	92	static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }