docs/fingerprint: Update JLink installation instructions
JLink can now be installed in the chroot with portage.
BRANCH=none
TEST=view in gitiles
@@ -32,17 +32,24 @@ used for JTAG and SWD for ARM devices.
is the only software required for flashing.
* In order to perform breakpoint debugging, you will need a tool that supports
connecting `gdbserver`. This document will assume [CLion] \(Googlers see
- [CLion for Chrome OS]) and was tested with `JLink_Linux_V684a_x86_64`.
- Alternatively, you can use [Ozone], a standalone debugger from Segger.
+ [CLion for Chrome OS]) and was tested with `JLink v6.94a`. Alternatively,
+ you can use [Ozone], a standalone debugger from Segger.
## JLink Software {#software}
-Download the [JLink Software], choosing the `J-Link Software and Documentation
-pack for Linux, TGZ archive, 64-bit` version. This version is recommended
-because it's simple to extract the tarball into a directory that is accessible
-to the Chrome OS chroot. The instructions in this document assume that you have
-extracted the tarball in
-`~/chromiumos/src/platform/ec/JLink_Linux_V684a_x86_64`.
+Install the JLink software in the chroot with the following command:
+
+```bash
+(chroot) $ sudo emerge jlink
+```
+
+<!-- mdformat off(b/139308852) -->
+*** note
+**NOTE**: The above command will print out a message directing you to manually
+download a tarball. You must follow these instructions for the installation to
+be complete.
+***
+<!-- mdformat on -->
## Connecting SWD {#connect-swd}
@@ -112,14 +119,14 @@ sensor runs at 1.8V. The pin is also not connected on the current designs.
```bash
# JLinkRemoteServerCLExe will listen on port 19020 (among others) by default.
# This can be overridden with the -Port argument.
-(outside) $ ./JLink_Linux_V684a_x86_64/JLinkRemoteServerCLExe -select USB
+(chroot) $ JLinkRemoteServerCLExe -select USB
```
You should see the following:
```bash
-SEGGER J-Link Remote Server V6.84a
-Compiled Sep 7 2020 18:28:13
+SEGGER J-Link Remote Server V6.94a
+Compiled Jan 14 2021 11:52:48
'q' to quit '?' for help
@@ -156,7 +163,7 @@ Start the JLink gdbserver for the appropriate MCU type:
* Icetower / [Nucleo STM32H743ZI]: `STM32H743ZI`
```bash
-(outside) $ ./JLink_Linux_V684a_x86_64/JLinkGDBServerCLExe -select USB -device STM32F412CG -endian little -if SWD -speed auto -noir -noLocalhostOnly
+(chroot) $ JLinkGDBServerCLExe -select USB -device STM32F412CG -endian little -if SWD -speed auto -noir -noLocalhostOnly
```
You should see the port that `gdbserver` is running on in the output:
@@ -164,7 +171,7 @@ You should see the port that `gdbserver` is running on in the output:
```bash
Connecting to J-Link...
J-Link is connected.
-Firmware: J-Trace PRO V2 Cortex-M compiled Dec 13 2019 11:19:22
+Firmware: J-Trace PRO V2 Cortex-M compiled Feb 5 2021 14:50:19
Hardware: V2.00
S/N: XXXXX
Feature(s): RDI, FlashBP, FlashDL, JFlash, GDB
