Merge tag 'signed-rpi-next' of git://github.com/agraf/u-boot

Patch queue for rpi - 2018-05-24

Some minor fixes for the Raspberry Pi:

  - Fix SD writes on new sdhost controller
  - Sanitize default load addresses, allowing for better payload placement

1 files changed, 36 insertions, 25 deletions

diff --git a/include/configs/rpi.h b/include/configs/rpi.h
index 69a22e1..649a425 100644
--- a/include/configs/rpi.h
+++ b/include/configs/rpi.h
@@ -95,39 +95,50 @@
  *
  * I suspect address 0 is used as the SMP pen on the RPi2, so avoid this.
  *
- * fdt_addr_r simply shouldn't overlap anything else. However, the RPi's
- *   binary firmware loads a DT to address 0x100, so we choose this address to
- *   match it. This allows custom boot scripts to pass this DT on to Linux
- *   simply by not over-writing the data at this address. When using U-Boot,
- *   U-Boot (and scripts it executes) typicaly ignore the DT loaded by the FW
- *   and loads its own DT from disk (triggered by boot.scr or extlinux.conf).
+ * Older versions of the boot firmware place the firmware-loaded DTB at 0x100,
+ * newer versions place it in high memory. So prevent U-Boot from doing its own
+ * DTB + initrd relocation so that we won't accidentally relocate the initrd
+ * over the firmware-loaded DTB and generally try to lay out things starting
+ * from the bottom of RAM.
  *
- * pxefile_addr_r can be pretty much anywhere that doesn't conflict with
- *   something else. Put it low in memory to avoid conflicts.
+ * kernel_addr_r has different constraints on ARM and Aarch64.  For 32-bit ARM,
+ * it must be within the first 128M of RAM in order for the kernel's
+ * CONFIG_AUTO_ZRELADDR option to work. The kernel itself will be decompressed
+ * to 0x8000 but the decompressor clobbers 0x4000-0x8000 as well. The
+ * decompressor also likes to relocate itself to right past the end of the
+ * decompressed kernel, so in total the sum of the compressed and and
+ * decompressed kernel needs to be reserved.
  *
- * kernel_addr_r must be within the first 128M of RAM in order for the
- *   kernel's CONFIG_AUTO_ZRELADDR option to work. Since the kernel will
- *   decompress itself to 0x8000 after the start of RAM, kernel_addr_r
- *   should not overlap that area, or the kernel will have to copy itself
- *   somewhere else before decompression. Similarly, the address of any other
- *   data passed to the kernel shouldn't overlap the start of RAM. Pushing
- *   this up to 16M allows for a sizable kernel to be decompressed below the
- *   compressed load address.
+ *   For Aarch64, the kernel image is uncompressed and must be loaded at
+ *   text_offset bytes (specified in the header of the Image) into a 2MB
+ *   boundary. The 'booti' command relocates the image if necessary. Linux uses
+ *   a default text_offset of 0x80000.  In summary, loading at 0x80000
+ *   satisfies all these constraints and reserving memory up to 0x02400000
+ *   permits fairly large (roughly 36M) kernels.
  *
- * scriptaddr can be pretty much anywhere that doesn't conflict with something
- *   else. Choosing 32M allows for the compressed kernel to be up to 16M.
+ * scriptaddr and pxefile_addr_r can be pretty much anywhere that doesn't
+ * conflict with something else. Reserving 1M for each of them at
+ * 0x02400000-0x02500000 and 0x02500000-0x02600000 should be plenty.
  *
- * ramdisk_addr_r simply shouldn't overlap anything else. Choosing 33M allows
- *   for any boot script to be up to 1M, which is hopefully plenty.
+ * On ARM, both the DTB and any possible initrd must be loaded such that they
+ * fit inside the lowmem mapping in Linux. In practice, this usually means not
+ * more than ~700M away from the start of the kernel image but this number can
+ * be larger OR smaller depending on e.g. the 'vmalloc=xxxM' command line
+ * parameter given to the kernel. So reserving memory from low to high
+ * satisfies this constraint again. Reserving 1M at 0x02600000-0x02700000 for
+ * the DTB leaves rest of the free RAM to the initrd starting at 0x02700000.
+ * Even with the smallest possible CPU-GPU memory split of the CPU getting
+ * only 64M, the remaining 25M starting at 0x02700000 should allow quite
+ * large initrds before they start colliding with U-Boot.
  */
 #define ENV_MEM_LAYOUT_SETTINGS \
 	"fdt_high=ffffffff\0" \
 	"initrd_high=ffffffff\0" \
-	"fdt_addr_r=0x00000100\0" \
-	"pxefile_addr_r=0x00100000\0" \
-	"kernel_addr_r=0x01000000\0" \
-	"scriptaddr=0x02000000\0" \
-	"ramdisk_addr_r=0x02100000\0" \
+	"kernel_addr_r=0x00080000\0" \
+	"scriptaddr=0x02400000\0" \
+	"pxefile_addr_r=0x02500000\0" \
+	"fdt_addr_r=0x02600000\0" \
+	"ramdisk_addr_r=0x02700000\0"
 
 #define BOOT_TARGET_DEVICES(func) \
 	func(MMC, mmc, 0) \