Update raspi5 baremetal examples all works and boots

2 files changed, 83 insertions, 44 deletions

diff --git a/md/index.md b/md/index.md
index 9bb36df..5b9d384 100644
--- a/md/index.md
+++ b/md/index.md
@@ -6,6 +6,7 @@ title: Writeup page
 
 <!-- Test [AM modulation](writeup/am_modulation.md)-->
 
+[Raspberry PI5 baremetal hello world](writeup/raspberry5_baremetal_helloworld.md)  
 [Kernel programming](notes/kernel/topics.md)  
 [QEMU ARM64](writeup/qemu_arm64.md)  
 [BladeRF quick guide](writeup/bladerf_quick_guide.md)  
diff --git a/md/writeup/raspberry5_baremetal_helloworld.md b/md/writeup/raspberry5_baremetal_helloworld.md
index ba5a575..6d31ca6 100644
--- a/md/writeup/raspberry5_baremetal_helloworld.md
+++ b/md/writeup/raspberry5_baremetal_helloworld.md
@@ -13,7 +13,6 @@ for your system.
 
 ## Source code
 
-
 ### boot.S
 
 ```
@@ -87,8 +86,34 @@ clean:
 	rm -rf *.o *.img *.elf
 ```
 
+
+### linker.ld
+```ld
+SECTIONS
+{
+    . = 0x80000;     /* Kernel load address for AArch64 */
+    .text : { KEEP(*(.text.boot)) *(.text .text.* .gnu.linkonce.t*) }
+    .rodata : { *(.rodata .rodata.* .gnu.linkonce.r*) }
+    PROVIDE(_data = .);
+    .data : { *(.data .data.* .gnu.linkonce.d*) }
+    .bss (NOLOAD) : {
+        . = ALIGN(16);
+        __bss_start = .;
+        *(.bss .bss.*)
+        *(COMMON)
+        __bss_end = .;
+    }
+    _end = .;
+
+   /DISCARD/ : { *(.comment) *(.gnu*) *(.note*) *(.eh_frame*) }
+}
+__bss_size = (__bss_end - __bss_start)>>3;
+```
+
 ### config.txt
 ```
+arm_64bit=1
+kernel=kernel8.img
 enable_jtag_gpio=1
 ```
 
@@ -99,12 +124,21 @@ make
 
 ### Prepare for a boot
 
-
+Create usual distro of your like. 
+Mount sdcard and backup original configs and original kernel. 
 
 ```sh
-cp
+cd /mnt/dir
+cp config.txt config.txt.bkp
+cp kernel8.img kernel8.img.original
 ```
 
+Copy kerne8.img and config.txt
+
+```sh
+cp /project/dir/config.txt /mnt/dir
+cp /project/dir/kernel8.img /mnt/dir
+```
 
 
 ## Debugging with OpenOCD+GDB
@@ -122,42 +156,45 @@ that suppose to work. Copy it for example in default openocd script location in:
 
 
 ```tcl
-# bcm2712.cfg
 # SPDX-License-Identifier: GPL-2.0-or-later
-# OpenOCD target config file
-# This file is based on target/bcm2711.cfg
-# I have checked that it works with Open On-Chip Debugger 0.12.0 
-# using the Raspberry Pi Debug-Probe interface
 
-transport select swd
-adapter speed 1000
+# The Broadcom BCM2712 used in Raspberry Pi 5
+# No documentation was found on Broadcom website
+
+# Partial information is available in Raspberry Pi website:
+# https://www.raspberrypi.com/documentation/computers/processors.html#bcm2712
+
+# v1.0 initial revision - trejan on forums.raspberrypi.com
 
 if { [info exists CHIPNAME] } {
-    set  _CHIPNAME $CHIPNAME
+        set  _CHIPNAME $CHIPNAME
 } else {
-    set  _CHIPNAME bcm2712
+        set  _CHIPNAME bcm2712
 }
 
 if { [info exists CHIPCORES] } {
-    set _cores $CHIPCORES
+        set _cores $CHIPCORES
 } else {
-    set _cores 4
+        set _cores 4
 }
 
 if { [info exists USE_SMP] } {
-    set _USE_SMP $USE_SMP
+        set _USE_SMP $USE_SMP
 } else {
-    set _USE_SMP 0
+        set _USE_SMP 0
 }
 
 if { [info exists DAP_TAPID] } {
-    set _DAP_TAPID $DAP_TAPID
+        set _DAP_TAPID $DAP_TAPID
 } else {
-    set _DAP_TAPID 0x2ba00477
+        set _DAP_TAPID 0x4ba00477
 }
 
-# swj_newdap $_CHIPNAME cpu -irlen 4 -ircapture 0x1 -irmask 0xf -expected-id $_DAP_TAPID
-swd newdap $_CHIPNAME cpu -expected-id $_DAP_TAPID
+transport select swd
+
+swd newdap $_CHIPNAME cpu -expected-id $_DAP_TAPID -irlen 4
+adapter speed 4000
+
 dap create $_CHIPNAME.dap -chain-position $_CHIPNAME.cpu
 
 # MEM-AP for direct access
@@ -170,17 +207,17 @@ set _CTIBASE {0x80020000 0x80120000 0x80220000 0x80320000}
 set _smp_command "target smp"
 
 for { set _core 0 } { $_core < $_cores } { incr _core } {
-    set _CTINAME $_CHIPNAME.cti$_core
-    set _TARGETNAME $_CHIPNAME.cpu$_core
+        set _CTINAME $_CHIPNAME.cti$_core
+        set _TARGETNAME $_CHIPNAME.cpu$_core
 
-    cti create $_CTINAME -dap $_CHIPNAME.dap -ap-num 0 -baseaddr [lindex $_CTIBASE $_core]
-    target create $_TARGETNAME aarch64 -dap $_CHIPNAME.dap -ap-num 0 -dbgbase [lindex $_DBGBASE $_core] -cti $_CTINAME
+        cti create $_CTINAME -dap $_CHIPNAME.dap -ap-num 0 -baseaddr [lindex $_CTIBASE $_core]
+        target create $_TARGETNAME aarch64 -dap $_CHIPNAME.dap -ap-num 0 -dbgbase [lindex $_DBGBASE $_core] -cti $_CTINAME
 
-    set _smp_command "$_smp_command $_TARGETNAME"
+        set _smp_command "$_smp_command $_TARGETNAME"
 }
 
 if {$_USE_SMP} {
-    eval $_smp_command
+        eval $_smp_command
 }
 
 # default target is cpu0
@@ -193,37 +230,38 @@ Connecting pico probe and doint step by step analysis of basic loop
 
 Start openocd server
 
-```
+```sh
 openocd -f interface/cmsis-dap.cfg -f target/bcm2712.cfg
 ```
 
-Connect with gdb
+Start gdb or gdb-multiarch
 
-```
+```sh
 gdb
 ```
 
+Restart the raspi5 with prepared files on sdcard
+
 and run inside gdb shell
 
-```
+```sh
 tar ext :3333
 ```
 
+ you should be connected to the openocd jtag session now press Ctrl+C
 
 ## Links
 
+https://www.raspberrypi.com/documentation/computers/config_txt.html  
+https://wiki.osdev.org/Raspberry_Pi_Bare_Bones  
+https://www.rpi4os.com/part1-bootstrapping/  
+https://www.valvers.com/open-software/raspberry-pi/bare-metal-programming-in-c-part-1/  
+https://www.raspberrypi.com/documentation/microcontrollers/debug-probe.html  
+https://macoy.me/blog/programming/RaspberryPi5Debugging  
+https://gist.github.com/tnishinaga/219122a5f1e3973668ee78c0fb1c7bf9  
+https://forums.raspberrypi.com/viewtopic.php?p=2172522#p2172522  
+https://github.com/DSERIOUSGUY/HobOS  
+https://developer.arm.com/documentation/ka006096/latest/  
+https://github.com/raspberrypi/firmware  
+https://ftp.gnu.org/old-gnu/Manuals/ld-2.9.1/html_mono/ld.html#SEC6
 
-https://www.raspberrypi.com/documentation/computers/config_txt.html
-https://wiki.osdev.org/Raspberry_Pi_Bare_Bones
-
-https://www.rpi4os.com/part1-bootstrapping/
-
-https://www.valvers.com/open-software/raspberry-pi/bare-metal-programming-in-c-part-1/
-
-https://www.raspberrypi.com/documentation/microcontrollers/debug-probe.html
-
-https://macoy.me/blog/programming/RaspberryPi5Debugging
-https://gist.github.com/tnishinaga/219122a5f1e3973668ee78c0fb1c7bf9
-https://forums.raspberrypi.com/viewtopic.php?p=2172522#p2172522
-
-https://github.com/DSERIOUSGUY/HobOS