Merge branch '2021-12-23-make-OF_BOARD-a-boolean' into next

Merge v8 of Simon's series to make CONFIG_OF_BOARD a boolean option.
Quoting him:

With Ilias' efforts we have dropped OF_PRIOR_STAGE and OF_HOSTFILE so
there are only three ways to obtain a devicetree:

   - OF_SEPARATE - the normal way, where the devicetree is built and
      appended to U-Boot
   - OF_EMBED - for development purposes, the devicetree is embedded in
      the ELF file (also used for EFI)
   - OF_BOARD - the board figures it out on its own

The last one is currently set up so that no devicetree is needed at all
in the U-Boot tree. Most boards do provide one, but some don't. Some
don't even provide instructions on how to boot on the board.

The problems with this approach were covered in another patch[1], since
removed from this series.

In practice, OF_BOARD is not really distinct from OF_SEPARATE. Any board
can obtain its devicetree at runtime, even it is has a devicetree built
in U-Boot. This is because U-Boot may be a second-stage bootloader and its
caller may have a better idea about the hardware available in the machine.
This is the case with a few QEMU boards, for example.

So it makes no sense to have OF_BOARD as a 'choice'. It should be an
option, available with either OF_SEPARATE or OF_EMBED. This would allow
rpi3, for example, to run with the devicetree provided by the prior
bootloader.

This series makes this change, adding various missing devicetree files
(and placeholders) to make the build work.

To make the 'prior stage' side of things more deterministic, a new
OF_HAS_PRIOR_STAGE is added, which cannot be disabled by updated a board's
defconfig. This should help to prevent mistakes.

It also adds a run-time message showing where the devicetree came from,
as well as warnings if the board's expected flow is not being used. This
comes originally from the 'standard passage' series, which depends on
this series.

It also provides a few qemu clean-ups discovered along the way. The
qemu-riscv64_spl problem is fixed.

Please see [2] for discussion on the v6 series.

I put Heinrich's Tested-by tag[3] for the series onto the three devicetree
patches (ARM and RISC-V) that I think it most affects. It isn't possible
to apply a tag to a whole series at present and in any case there are
changes in v7.

This series is available at u-boot-dm/ofb-working

[1] https://patchwork.ozlabs.org/project/uboot/patch/[email protected]/
[2] https://lore.kernel.org/u-boot/20211205133207.GW1220664@bill-the-cat/T/#mcd8c0258827fbc1bb3000b7ff9ba0929df1ddcb2
[3] https://lore.kernel.org/u-boot/[email protected]/raw

6 files changed, 90 insertions, 3 deletions

diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index 16fd305a65c..104282bd479 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -244,6 +244,10 @@ struct global_data {
 	 * @fdt_size: space reserved for relocated device space
 	 */
 	unsigned long fdt_size;
+	/**
+	 * @fdt_src: Source of FDT
+	 */
+	enum fdt_source_t fdt_src;
 #if CONFIG_IS_ENABLED(OF_LIVE)
 	/**
 	 * @of_root: root node of the live tree
@@ -512,6 +516,14 @@ static_assert(sizeof(struct global_data) == GD_SIZE);
 #define gd_acpi_ctx()		NULL
 #endif
 
+#if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
+#define gd_multi_dtb_fit()	gd->multi_dtb_fit
+#define gd_set_multi_dtb_fit(_dtb)	gd->multi_dtb_fit = _dtb
+#else
+#define gd_multi_dtb_fit()	NULL
+#define gd_set_multi_dtb_fit(_dtb)
+#endif
+
 /**
  * enum gd_flags - global data flags
  *
diff --git a/include/dm/device.h b/include/dm/device.h
index 544734ecb31..cf785f7ae21 100644
--- a/include/dm/device.h
+++ b/include/dm/device.h
@@ -593,7 +593,7 @@ int device_get_child(const struct udevice *parent, int index,
 		     struct udevice **devp);
 
 /**
- * device_get_child_count() - Get the available child count of a device
+ * device_get_child_count() - Get the child count of a device
  *
  * Returns the number of children to a device.
  *
@@ -602,6 +602,15 @@ int device_get_child(const struct udevice *parent, int index,
 int device_get_child_count(const struct udevice *parent);
 
 /**
+ * device_get_decendent_count() - Get the total number of decendents of a device
+ *
+ * Returns the total number of decendents, including all children
+ *
+ * @parent:	Parent device to check
+ */
+int device_get_decendent_count(const struct udevice *parent);
+
+/**
  * device_find_child_by_seq() - Find a child device based on a sequence
  *
  * This searches for a device with the given seq.
diff --git a/include/dm/root.h b/include/dm/root.h
index 42510b106ab..780f269db65 100644
--- a/include/dm/root.h
+++ b/include/dm/root.h
@@ -131,4 +131,12 @@ int dm_remove_devices_flags(uint flags);
 static inline int dm_remove_devices_flags(uint flags) { return 0; }
 #endif
 
+/**
+ * dm_get_stats() - Get some stats for driver mode
+ *
+ * @device_countp: Returns total number of devices that are bound
+ * @uclass_countp: Returns total number of uclasses in use
+ */
+void dm_get_stats(int *device_countp, int *uclass_countp);
+
 #endif
diff --git a/include/dm/uclass-internal.h b/include/dm/uclass-internal.h
index 49808c5c856..fb0edcc2969 100644
--- a/include/dm/uclass-internal.h
+++ b/include/dm/uclass-internal.h
@@ -307,6 +307,13 @@ static inline int uclass_pre_remove_device(struct udevice *dev) { return 0; }
 #endif
 
 /**
+ * uclass_get_count() - Get the number of uclasses
+ *
+ * Returns the number of uclasses instantiated in driver model
+ */
+int uclass_get_count(void);
+
+/**
  * uclass_find() - Find uclass by its id
  *
  * @id:		Id to serach for
diff --git a/include/dt-bindings/clock/bcm2835.h b/include/dt-bindings/clock/bcm2835.h
index 2cec01f9689..b60c03430cf 100644
--- a/include/dt-bindings/clock/bcm2835.h
+++ b/include/dt-bindings/clock/bcm2835.h
@@ -58,3 +58,5 @@
 #define BCM2835_CLOCK_DSI1E		48
 #define BCM2835_CLOCK_DSI0P		49
 #define BCM2835_CLOCK_DSI1P		50
+
+#define BCM2711_CLOCK_EMMC2		51
diff --git a/include/fdtdec.h b/include/fdtdec.h
index 6c7ab887b20..09525ce510a 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -55,6 +55,31 @@ struct bd_info;
 #define SPL_BUILD	0
 #endif
 
+/**
+ * enum fdt_source_t - indicates where the devicetree came from
+ *
+ * These are listed in approximate order of desirability after FDTSRC_NONE
+ *
+ * @FDTSRC_SEPARATE: Appended to U-Boot. This is the normal approach if U-Boot
+ *	is the only firmware being booted
+ * @FDTSRC_FIT: Found in a multi-dtb FIT. This should be used when U-Boot must
+ *	select a devicetree from many options
+ * @FDTSRC_BOARD: Located by custom board code. This should only be used when
+ *	the prior stage does not support FDTSRC_PASSAGE
+ * @FDTSRC_EMBED: Embedded into U-Boot executable. This should onyl be used when
+ *	U-Boot is packaged as an ELF file, e.g. for debugging purposes
+ * @FDTSRC_ENV: Provided by the fdtcontroladdr environment variable. This should
+ *	be used for debugging/development only
+ * @FDTSRC_NONE: No devicetree at all
+ */
+enum fdt_source_t {
+	FDTSRC_SEPARATE,
+	FDTSRC_FIT,
+	FDTSRC_BOARD,
+	FDTSRC_EMBED,
+	FDTSRC_ENV,
+};
+
 /*
  * Information about a resource. start is the first address of the resource
  * and end is the last address (inclusive). The length of the resource will
@@ -111,6 +136,20 @@ struct fdt_pci_addr {
 extern u8 __dtb_dt_begin[];	/* embedded device tree blob */
 extern u8 __dtb_dt_spl_begin[];	/* embedded device tree blob for SPL/TPL */
 
+/* Get a pointer to the embedded devicetree, if there is one, else NULL */
+static inline u8 *dtb_dt_embedded(void)
+{
+#ifdef CONFIG_OF_EMBED
+# ifdef CONFIG_SPL_BUILD
+	return __dtb_dt_spl_begin;
+# else
+	return __dtb_dt_begin;
+# endif
+#else
+	return NULL;
+#endif
+}
+
 /**
  * Compute the size of a resource.
  *
@@ -1156,10 +1195,13 @@ int fdtdec_resetup(int *rescan);
 
 /**
  * Board-specific FDT initialization. Returns the address to a device tree blob.
- * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
- * and the board implements it.
+ *
+ * Called when CONFIG_OF_BOARD is defined.
+ *
+ * The existing devicetree is available at gd->fdt_blob
  *
  * @err internal error code if we fail to setup a DTB
+ * @returns new devicetree blob pointer
  */
 void *board_fdt_blob_setup(int *err);
 
@@ -1198,4 +1240,11 @@ int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
 			   phys_addr_t *basep, phys_size_t *sizep,
 			   struct bd_info *bd);
 
+/**
+ * fdtdec_get_srcname() - Get the name of where the devicetree comes from
+ *
+ * @return source name
+ */
+const char *fdtdec_get_srcname(void);
+
 #endif