docs: Add README for booting instructions for all devices

Add README for booting instructions for all devices with supported
boot mediums.

Signed-off-by: Sandeep Gundlupet Raju <sandeep.gundlupet-raju@amd.com>
Signed-off-by: Mark Hatle <mark.hatle@amd.com>

1 files changed, 212 insertions, 0 deletions

diff --git a/docs/README.booting.zynqmp.md b/docs/README.booting.zynqmp.md
new file mode 100644
index 00000000..c8f8aa21
--- /dev/null
+++ b/docs/README.booting.zynqmp.md
@@ -0,0 +1,212 @@
+# Booting OS Images on ZynqMP target boards
+
+Booting OS images on ZynqMP boards can be done using JTAG, SD, eMMC, QSPI and 
+NAND boot modes.
+
+* [Setting Up the Target](#setting-up-the-target)
+* [Booting from JTAG](#booting-from-jtag)
+  * [Loading boot components using XSCT](#loading-boot-components-using-xsct)
+  * [Loading Kernel, Root Filesystem and U-boot boot script](#loading-kernel-root-filesystem-and-u-boot-boot-script)
+    * [Using XSCT](#using-xsct)
+    * [Using TFTP](#using-tftp)
+* [Booting from SD](#booting-from-sd)
+* [Booting from QSPI](#booting-from-qspi)
+
+## Setting Up the Target
+1. Connect a USB cable between the CP2180 USB-to-Quad-UART bridge USB Micro-B on
+   the target and the USB port on the host machine.
+2. Connect a micro USB cable from the ZCU102 board USB UART port (J83) to the USB
+   port on the host machine.
+3. Default UART terminal(serial port) settings is Speed `115200`, Data `8 bit`,
+   Parity `None`, Stop bits ` 1 bit` and Flow control `None`.
+4. Set the board to JTAG and other boot mode by setting the boot mode switch by 
+   referring to board user guide. For zynqmp-generic machine configuration
+   file zcu102 evaluation board is used as reference and below is the
+   configuration boot mode settings (SW6).
+
+> **Note:** Switch OFF = 1 = High; ON = 0 = Low
+
+| Boot Mode | Mode Pins [3:0] | Mode SW6 [3:0]    | Comments                  |
+|-----------|-----------------|-------------------|---------------------------|
+| JTAG      | 0000            | ON, ON, ON, ON    | PS JTAG                   |
+| QSPI      | 0010            | ON, ON, OFF, ON   | QSPI 32-bit addressing    |
+| SD        | 1110            | OFF, OFF, OFF, ON | SD 3.0 with level shifter |
+
+## Booting from JTAG
+
+This boot flow requires the use of the AMD Xilinx tools, specifically XSCT and 
+the associated JTAG device drivers. This also requires access to the JTAG interface
+on the board, a number of AMD Xilinx and third-party boards come with on-board JTAG
+modules.
+
+1. Source the Vivado or Vitis tools `settings.sh` scripts.
+2. Power on the board, Open the XSCT console in the Vitis IDE by clicking the
+   XSCT button. Alternatively, you can also open the XSCT console by selecting
+   Xilinx -> XSCT Console.
+```
+$ xsct
+```
+3. In the XSCT console, connect to the target over JTAG using the connect command.
+   Optionally user can use `-url` to specify the local/remote hw_server. The 
+   connect command returns the channel ID of the connection.
+```
+xsct% connect
+```
+4. The targets command lists the available targets and allows you to select a
+   target using its ID. The targets are assigned IDs as they are discovered on
+   the JTAG chain, so the IDs can change from session to session.
+```
+xsct% targets
+```
+
+> **Note:** For non-interactive usage such as scripting, you can use the `-filter`
+   option to select a target instead of selecting the target using its ID.
+
+### Loading boot components using XSCT
+
+1. Download the boot images for the target using XSCT with the `fpga` and `dow` 
+   command. ZyqnMP boot images will be located in the `${DEPLOY_DIR_IMAGE}`
+   directory. 
+
+> **Note:** In yocto by default, ${DEPLOY_DIR_IMAGE}/system.dtb is used for both
+> u-boot and kernel.
+
+2. Program the bitstream or skip this step if you are loading from u-boot or linux.
+```
+xsct% fpga -no-revision-check ${DEPLOY_DIR_IMAGE}/download.bit
+```
+3. By default, JTAG security gates are enabled. Disable the security gates for 
+   DAP, PL TAP, and PMU (this makes the PMU MB target visible to the debugger).
+```
+xsct% targets -set -nocase -filter {name =~ "*PSU*"}
+xsct% mask_write 0xFFCA0038 0x1C0 0x1C0
+```
+3. Verify if the PMU MB target is listed under the PMU device. Now, load the PMU
+   firmware.
+```
+xsct% targets -set -nocase -filter {name =~ "*MicroBlaze PMU*"}
+xsct% catch {stop}
+xsct% dow ${DEPLOY_DIR_IMAGE}/pmufw.elf
+xsct% con
+```
+5. Reset APU Cortex-A53 Core 0 to load and execute FSBL, This step is important, 
+   because when the ZynqMP boots up in JTAG boot mode, all the APU and RPU cores
+   are held in reset. You must clear the resets on each core before performing 
+   debugging on these cores. You can use the `rst` command in XSCT to clear the
+   resets.
+```
+xsct% targets -set -nocase -filter {name =~ "*A53*#0"}
+xsct% rst -processor -clear-registers
+```
+6. Download and run FSBL from APU Cortex-A53 Core 0
+```
+xsct% dow ${DEPLOY_DIR_IMAGE}/zynqmp_fsbl.elf
+xsct% con
+```
+7. Now download TF-A, U-boot.elf and Device tree to APU and execute.
+```
+xsct% stop
+xsct% dow ${DEPLOY_DIR_IMAGE}/bl31.elf
+xsct% dow ${DEPLOY_DIR_IMAGE}/u-boot.elf
+xsct% dow -data ${DEPLOY_DIR_IMAGE}/system.dtb 0x100000
+xsct% con
+```
+
+8. In the target Serial Terminal, press any key to stop the U-Boot auto-boot.
+```
+...
+Hit any key to stop autoboot: 0
+U-Boot>
+```
+
+### Loading Kernel, Root Filesystem and U-boot boot script
+
+Load the images into the target DDR/PL DRR load address i.e.,
+`DDR base address + <image_offset>`. 
+
+Below example uses base DDR address as 0x0 which matches in vivado address editor.
+
+| Image Type         | Base DDR Address | Image Offset | Load Address in DDR |
+|--------------------|------------------|--------------|---------------------|
+| Kernel             | 0x0              | 0x200000     | 0x200000            |
+| Device Tree        | 0x0              | 0x1000       | 0x1000              |
+| Rootfs             | 0x0              | 0x04000000   | 0x4000000           |
+| U-boot boot script | 0x0              | 0x20000000   | 0x20000000          |
+
+> **Note:** 
+> 1. `<target-image>` refers to core-image-minimal or petalinux-image-minimal
+> 2. For pxeboot boot create a symlink for `<target-image>-${MACHINE}-${DATETIME}.cpio.gz.u-boot`
+> as shown `$ ln -sf ${DEPLOY_DIR_IMAGE}/<target-image>-${MACHINE}-${DATETIME}.cpio.gz.u-boot ${DEPLOY_DIR_IMAGE}/rootfs.cpio.gz.u-boot`
+> to ensure the INITRD name in pxeboot.cfg matches with image name.
+> 3. Whilst it is possible to load the images via JTAG this connection is slow and
+this process can take a long time to execute (more than 10 minutes). If your
+system has ethernet it is recommended that you use TFTP to load these images
+using U-Boot. 
+> 4. If common ${DEPLOY_DIR_IMAGE}/system.dtb is used by u-boot and kernel, this
+> is already part of boot.bin we can skip loading dtb, else load kernel dtb.
+
+#### Using XSCT
+
+1. Suspend the execution of active target using `stop` command in XSCT.
+```
+xsct% stop
+```
+2. Using the `dow` command to load the images into the target DDR/PL DDR load 
+   address.
+```
+xsct% dow -data ${DEPLOY_DIR_IMAGE}/Image 0x200000
+xsct% dow -data ${DEPLOY_DIR_IMAGE}/system.dtb 0x100000
+xsct% dow -data ${DEPLOY_DIR_IMAGE}/core-image-minimal-${MACHINE}.cpio.gz.u-boot 0x4000000
+xsct% dow -data ${DEPLOY_DIR_IMAGE}/boot.scr 0x20000000
+```
+
+#### Using TFTP
+
+1. Configure the `ipaddr` and `serverip` of the U-Boot environment. 
+```
+Versal> set serverip <server ip>
+Versal> set ipaddr <board ip>
+```
+2. Load the images to DDR address. Make sure images are copied to tftp directory.
+```
+U-Boot> tftpboot 0x200000 ${TFTPDIR}/Image
+U-Boot> tftpboot 0x100000 ${TFTPDIR}/system.dtb
+U-Boot> tftpboot 0x4000000 ${TFTPDIR}/core-image-minimal-${MACHINE}.cpio.gz.u-boot
+U-Boot> tftpboot 0x20000000 ${TFTPDIR}/boot.scr
+
+```
+### Booting Linux
+
+Once the images are loaded continue the execution.
+
+1. After loading images resume the execution of active target using the `con`
+command in XSCT shell, Skip step 1 for if you have used TFTP to load images.
+```
+xsct% con
+```
+2. Terminate xsct shell.
+```
+xsct% exit
+```
+3. In the target Serial Terminal, from U-Boot prompt run `boot` command.
+```
+U-Boot> boot
+```
+
+## Booting from SD
+
+1. Load the SD card into the ZCU102 board in the J100 SD slot.
+2. Configure the ZCU102 board to boot in SD-Boot mode (1-ON, 2-OFF, 3-OFF, 4-OFF)
+   by setting the SW6. Refer [Setting Up the Target](#setting-up-the-target).
+3. Follow SD boot instructions [README](README.booting.storage.md) for more details.
+
+## Booting from QSPI
+
+1. To boot ZCU012 board in QSPI boot mode, Power on the ZCU102 board and boot 
+   using JTAG or SD boot mode, to ensure that U-Boot is running and also have 
+   boot.bin copied to DDR location using XSCT `dow` or `tftpboot` or `fatload`
+   command.
+2. Follow Flash boot instructions [README](README.booting.flash.md) for more details.
+3. After flashing the images, turn off the power switch on the board, and change
+   the SW6 boot mode pin settings to QSPI boot mode (1-ON, 2-ON, 3-OFF, 4-ON) by
+   setting the SW6. Refer [Setting Up the Target](#setting-up-the-target).
\ No newline at end of file