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

1 files changed, 83 insertions, 58 deletions

diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 7681f272d27..280cda61a72 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -76,6 +76,19 @@ static const char * const compat_names[COMPAT_COUNT] = {
 	COMPAT(ALTERA_SOCFPGA_CLK_INIT, "altr,socfpga-a10-clk-init")
 };
 
+static const char *const fdt_src_name[] = {
+	[FDTSRC_SEPARATE] = "separate",
+	[FDTSRC_FIT] = "fit",
+	[FDTSRC_BOARD] = "board",
+	[FDTSRC_EMBED] = "embed",
+	[FDTSRC_ENV] = "env",
+};
+
+const char *fdtdec_get_srcname(void)
+{
+	return fdt_src_name[gd->fdt_src];
+}
+
 const char *fdtdec_get_compatible(enum fdt_compat_id id)
 {
 	/* We allow reading of the 'unknown' ID for testing purposes */
@@ -1146,11 +1159,10 @@ int fdtdec_setup_mem_size_base_lowest(void)
 	return 0;
 }
 
-#if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
-# if CONFIG_IS_ENABLED(MULTI_DTB_FIT_GZIP) ||\
-	CONFIG_IS_ENABLED(MULTI_DTB_FIT_LZO)
 static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
 {
+#if CONFIG_IS_ENABLED(MULTI_DTB_FIT_GZIP) ||\
+	CONFIG_IS_ENABLED(MULTI_DTB_FIT_LZO)
 	size_t sz_out = CONFIG_VAL(MULTI_DTB_FIT_UNCOMPRESS_SZ);
 	bool gzip = 0, lzo = 0;
 	ulong sz_in = sz_src;
@@ -1175,11 +1187,11 @@ static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
 			return -ENOMEM;
 		}
 	} else  {
-#  if CONFIG_IS_ENABLED(MULTI_DTB_FIT_USER_DEFINED_AREA)
+# if CONFIG_IS_ENABLED(MULTI_DTB_FIT_USER_DEFINED_AREA)
 		dst = (void *)CONFIG_VAL(MULTI_DTB_FIT_USER_DEF_ADDR);
-#  else
+# else
 		return -ENOTSUPP;
-#  endif
+# endif
 	}
 
 	if (CONFIG_IS_ENABLED(GZIP) && gzip)
@@ -1197,27 +1209,22 @@ static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
 		return -EBADMSG;
 	}
 	*dstp = dst;
-	return 0;
-}
-# else
-static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
-{
+#else
+	*dstp = (void *)src;
 	*dstp = (void *)src;
+#endif
 	return 0;
 }
-# endif
-#endif
 
-#if defined(CONFIG_OF_BOARD) || defined(CONFIG_OF_SEPARATE)
-/*
- * For CONFIG_OF_SEPARATE, the board may optionally implement this to
- * provide and/or fixup the fdt.
+/**
+ * fdt_find_separate() - Find a devicetree at the end of the image
+ *
+ * @return pointer to FDT blob
  */
-__weak void *board_fdt_blob_setup(int *err)
+static void *fdt_find_separate(void)
 {
 	void *fdt_blob = NULL;
 
-	*err = 0;
 #ifdef CONFIG_SPL_BUILD
 	/* FDT is at end of BSS unless it is in a different memory region */
 	if (IS_ENABLED(CONFIG_SPL_SEPARATE_BSS))
@@ -1231,7 +1238,6 @@ __weak void *board_fdt_blob_setup(int *err)
 
 	return fdt_blob;
 }
-#endif
 
 int fdtdec_set_ethernet_mac_address(void *fdt, const u8 *mac, size_t size)
 {
@@ -1589,60 +1595,81 @@ int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
 	return 0;
 }
 
+/* TODO([email protected]): This function should not be weak */
 __weak int fdtdec_board_setup(const void *fdt_blob)
 {
 	return 0;
 }
 
-int fdtdec_setup(void)
+/**
+ * setup_multi_dtb_fit() - locate the correct dtb from a FIT
+ *
+ * This supports the CONFIG_MULTI_DTB_FIT feature, looking for the dtb in a
+ * supplied FIT
+ *
+ * It accepts the current value of gd->fdt_blob, which points to the FIT, then
+ * updates that gd->fdt_blob, to point to the chosen dtb so that U-Boot uses the
+ * correct one
+ */
+static void setup_multi_dtb_fit(void)
 {
-	int ret;
-#if CONFIG_IS_ENABLED(OF_CONTROL)
-# if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
-	void *fdt_blob;
-# endif
-# ifdef CONFIG_OF_EMBED
-	/* Get a pointer to the FDT */
-#  ifdef CONFIG_SPL_BUILD
-	gd->fdt_blob = __dtb_dt_spl_begin;
-#  else
-	gd->fdt_blob = __dtb_dt_begin;
-#  endif
-# elif defined(CONFIG_OF_BOARD) || defined(CONFIG_OF_SEPARATE)
-	/* Allow the board to override the fdt address. */
-	gd->fdt_blob = board_fdt_blob_setup(&ret);
-	if (ret)
-		return ret;
-# endif
-# ifndef CONFIG_SPL_BUILD
-	/* Allow the early environment to override the fdt address */
-	gd->fdt_blob = map_sysmem
-		(env_get_ulong("fdtcontroladdr", 16,
-			       (unsigned long)map_to_sysmem(gd->fdt_blob)), 0);
-# endif
+	void *blob;
 
-# if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
 	/*
 	 * Try and uncompress the blob.
 	 * Unfortunately there is no way to know how big the input blob really
 	 * is. So let us set the maximum input size arbitrarily high. 16MB
 	 * ought to be more than enough for packed DTBs.
 	 */
-	if (uncompress_blob(gd->fdt_blob, 0x1000000, &fdt_blob) == 0)
-		gd->fdt_blob = fdt_blob;
+	if (uncompress_blob(gd->fdt_blob, 0x1000000, &blob) == 0)
+		gd->fdt_blob = blob;
 
 	/*
 	 * Check if blob is a FIT images containings DTBs.
 	 * If so, pick the most relevant
 	 */
-	fdt_blob = locate_dtb_in_fit(gd->fdt_blob);
-	if (fdt_blob) {
-		gd->multi_dtb_fit = gd->fdt_blob;
-		gd->fdt_blob = fdt_blob;
+	blob = locate_dtb_in_fit(gd->fdt_blob);
+	if (blob) {
+		gd_set_multi_dtb_fit(gd->fdt_blob);
+		gd->fdt_blob = blob;
+		gd->fdt_src = FDTSRC_FIT;
 	}
+}
 
-# endif
-#endif
+int fdtdec_setup(void)
+{
+	int ret;
+
+	/* The devicetree is typically appended to U-Boot */
+	if (IS_ENABLED(CONFIG_OF_SEPARATE)) {
+		gd->fdt_blob = fdt_find_separate();
+		gd->fdt_src = FDTSRC_SEPARATE;
+	} else { /* embed dtb in ELF file for testing / development */
+		gd->fdt_blob = dtb_dt_embedded();
+		gd->fdt_src = FDTSRC_EMBED;
+	}
+
+	/* Allow the board to override the fdt address. */
+	if (IS_ENABLED(CONFIG_OF_BOARD)) {
+		gd->fdt_blob = board_fdt_blob_setup(&ret);
+		if (ret)
+			return ret;
+		gd->fdt_src = FDTSRC_BOARD;
+	}
+
+	/* Allow the early environment to override the fdt address */
+	if (!IS_ENABLED(CONFIG_SPL_BUILD)) {
+		ulong addr;
+
+		addr = env_get_hex("fdtcontroladdr", 0);
+		if (addr) {
+			gd->fdt_blob = map_sysmem(addr, 0);
+			gd->fdt_src = FDTSRC_ENV;
+		}
+	}
+
+	if (CONFIG_IS_ENABLED(MULTI_DTB_FIT))
+		setup_multi_dtb_fit();
 
 	ret = fdtdec_prepare_fdt();
 	if (!ret)
@@ -1650,7 +1677,6 @@ int fdtdec_setup(void)
 	return ret;
 }
 
-#if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
 int fdtdec_resetup(int *rescan)
 {
 	void *fdt_blob;
@@ -1661,8 +1687,8 @@ int fdtdec_resetup(int *rescan)
 	 * FIT image stillpresent there. Save the time and space
 	 * required to uncompress it again.
 	 */
-	if (gd->multi_dtb_fit) {
-		fdt_blob = locate_dtb_in_fit(gd->multi_dtb_fit);
+	if (gd_multi_dtb_fit()) {
+		fdt_blob = locate_dtb_in_fit(gd_multi_dtb_fit());
 
 		if (fdt_blob == gd->fdt_blob) {
 			/*
@@ -1686,7 +1712,6 @@ int fdtdec_resetup(int *rescan)
 	*rescan = 0;
 	return 0;
 }
-#endif
 
 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
 			   phys_addr_t *basep, phys_size_t *sizep,