Documentation/tutorial/part2.md - platform/external/coreboot - Git at Google

 # Tutorial, part 2: Submitting a patch to coreboot.org

 ## Step 1: Set up an account at coreboot.org

 If you already have an account, skip to Step 2.

 Otherwise, go to <https://review.coreboot.org> in your preferred web
 browser.  Select **Sign in** in the upper right corner.

 Select the appropriate sign-in. For example, if you have a Google
 account, select **Google OAuth2** (gerrit-oauth-provider plugin).
 **Note:** Your username for the account will be the username of the
 account you used to sign-in with. (ex. your Google username).

 ## Step 2a: Set up SSH keys

 If you prefer to use an HTTP password instead, skip to Step 2b.

 If you do not have an SSH key set up on your account already (as is the
 case with a newly created account), follow the instructions below;
 otherwise, doing so could overwrite an existing key.

 In a terminal, run `ssh-keygen -t ed25519` and confirm the default path
 `.ssh/id_ed25519`.

 Make a passphrase -- remember this phrase. It will be needed whenever
 you use this public key. **Note:** You might want to use a short
 password, or forego the password altogether as you will be using it very
 often.

 Copy the content of `.ssh/id_ed25519.pub` (notice the ".pub" suffix
 as you need to send the public key) into the textbox "New SSH Key" at
 <https://review.coreboot.org/settings/#SSHKeys> and save it.

 ## Step 2b: Set up an HTTP Password

 Alternatively, instead of using SSH keys, you can use an HTTP password.
 To do so, after you select your name and click on **Settings** on the
 left-hand side, rather than selecting **SSH Public Keys**, select **HTTP
 Password**.

 Click **Generate Password**. This should fill the "Password" box with a
 password. Copy the password, and add the following to your
 `$HOME/.netrc` file:

 	machine review.coreboot.org login YourUserNameHere password YourPasswordHere

 where YourUserNameHere is your username, and YourPasswordHere is the
 password you just generated.

 If your system is behind a snooping HTTPS proxy, you might also have to
 make its SSL certificate known to curl, a system specific operation.
 If that's not possible for some reason, you can also disable SSL
 certificate verification in git:

 	git config [--global] http.sslVerify [true|false]

 The `--global` argument sets it for all git transfers of your local
 user, `false` means not to validate the certificate.

 If that still doesn't allow you to pull or push changes to the server,
 the proxy is likely tampering with the data stream, in which case
 there's nothing we can do.

 ## Step 3: Clone coreboot and configure it for submitting patches

 On Gerrit, click on the **Browse** tab in the upper left corner and
 select **Repositories**. From the listing, select the "coreboot" repo.
 You may have to click the next page arrow at the bottom a few times to
 find it.

 If you are using SSH keys, select **ssh** from the tabs under "Project
 coreboot" and run the "clone with commit-msg hook" command that's
 provided.  This should prompt you for your id_rsa passphrase, if you
 previously set one.

 **Note:** if the **ssh** option is not showing, check that you have a
 username set. Click the profile picture at the top right and select
 **User Settings**, then set your username in the **Profile** section.

 If you are using HTTP, instead, select **http** from the tabs under
 "Project coreboot" and run the command that appears.

 Now is a good time to configure your global git identity, if you haven't
 already.

 	git config --global user.name "Your Name"
 	git config --global user.email "Your Email"

 Finally, enter the local git repository and set up repository specific
 hooks and other configurations.

 	cd coreboot
 	make gitconfig

 ## Step 4: Submit a commit

 An easy first commit to make is fixing existing checkpatch errors and
 warnings in the source files. To see errors that are already present,
 build the files in the repository by running `make lint` in the coreboot
 directory. Alternatively, if you want to run `make lint` on a specific
 directory, run:

 	util/lint/lint-007-checkpatch <filepath>

 where `filepath` is the filepath of the directory (ex.
 `src/cpu/amd/car`).

 Any changes made to files under the src directory are made locally,
 and can be submitted for review.

 Once you finish making your desired changes, use the command line to
 stage and submit your changes. An alternative and potentially easier way
 to stage and submit commits is to use git cola, a graphical user
 interface for git. For instructions on how to do so, skip to Step 4b.

 ## Step 4a: Use the command line to stage and submit a commit

 To use the command line to stage a commit, run

 	git add <filename>

 where `filename` is the name of your file.

 To commit the change, run

 	git commit -s

 **Note:** The -s adds a signed-off-by line by the committer. Your commit
 should be signed off with your name and email (i.e. **Your Name**
 **\<Your Email\>**, based on what you set with git config earlier).

 Running git commit first checks for any errors and warnings using lint.
 If there are any, you must go back and fix them before submitting your
 commit.  You can do so by making the necessary changes, and then staging
 your commit again.

 When there are no errors or warnings, your default text editor will
 open.  This is where you will write your commit message.

 The first line of your commit message is your commit summary. This is a
 brief one-line description of what you changed in the files using the
 template below:

     <filepath>: Short description

 For example,

     cpu/amd/pi/00630F01: Fix checkpatch warnings and errors

 **Note:** It is good practice to use present tense in your descriptions
 and do not punctuate your summary.

 Then hit Enter. The next paragraph should be a more in-depth explanation
 of the changes you've made to the files. Again, it is good practice to
 use present tense. Ex.

     Fix space prohibited between function name and open parenthesis,
     line over 80 characters, unnecessary braces for single statement
     blocks, space required before open brace errors and warnings.

 When you have finished writing your commit message, save and exit the
 text editor. You have finished committing your change. If, after
 submitting your commit, you wish to make changes to it, running `git
 commit --amend` allows you to take back your commit and amend it.

 When you are done with your commit, run `git push` to push your commit
 to coreboot.org. **Note:** To submit as a private patch, use `git push
 origin HEAD:refs/for/main%private`. Submitting as a private patch
 means that your commit will be on review.coreboot.org, but is only
 visible to yourself and those you add as reviewers. This mode isn't
 perfect: Somebody who knows the commit ID can still fetch the change and
 everything it refers (e.g.  parent commits).

 This has been a quick primer on how to submit a change to Gerrit for
 review using git. You may wish to review the [Gerrit code review
 workflow
 documentation](https://gerrit-review.googlesource.com/Documentation/intro-user.html#code-review),
 especially if you plan to work on multiple changes at the same time.

 ## Step 4b: Use git cola to stage and submit a commit

 If git cola is not installed on your machine, see
 <https://git-cola.github.io/downloads.html> for download instructions.

 After making some edits to src files, rather than run `git add`, run
 `git cola` from the command line. You should see all of the files
 edited under "Modified".

 In the textbox labeled "Commit summary" provide a brief one-line
 description of what you changed in the files according to the template
 below:

     <filepath>: Short description

 For example,

     cpu/amd/pi/00630F01: Fix checkpatch warnings and errors

 **Note:** It is good practice to use present tense in your descriptions
 and do not punctuate your short description.

 In the larger text box labeled 'Extended description...' provide a more
 in-depth explanation of the changes you've made to the files. Again, it
 is good practice to use present tense. Ex.

     Fix space prohibited between function name and open parenthesis,
     line over 80 characters, unnecessary braces for single statement
     blocks, space required before open brace errors and warnings.

 Then press Enter two times to move the cursor to below your description.
 To the left of the text boxes, there is an icon with an downward arrow.
 Press the arrow and select "Sign Off." Make sure that you are signing
 off with your name and email (i.e. **Your Name** **\<Your Email\>**,
 based on what you set with git config earlier).

 Now, review each of your changes and mark either individual changes or
 an entire file as Ready to Commit by marking it as 'Staged'. To do
 this, select one file from the 'Modified' list. If you only want to
 submit particular changes from each file, then highlight the red and
 green lines for your changes, right click and select 'Stage Selected
 Lines'. Alternatively, if an entire file is ready to be committed, just
 double click on the file under 'Modified' and it will be marked as
 Staged.

 Once the descriptions are done and all the edits you would like to
 commit have been staged, press 'Commit' on the right of the text
 boxes.

 If the commit fails due to persisting errors, a text box will appear
 showing the errors. You can correct these errors within 'git cola' by
 right-clicking on the file in which the error occurred and selecting
 'Launch Diff Tool'. Make necessary corrections, close the Diff Tool and
 'Stage' the corrected file again. It might be necessary to refresh
 'git cola' in order for the file to be shown under 'Modified' again.
 Note: Be sure to add any other changes that haven't already been
 explained in the extended description.

 When ready, select 'Commit' again. Once all errors have been satisfied
 and the commit succeeds, move to the command line and run `git push`.

 ## Step 5: Let others review your commit

 Your commits can now be seen on review.coreboot.org if you select "Your"
 and click on "Changes" and can be reviewed by others. Your code will
 first be reviewed by build bot (Jenkins), which will either give you a
 warning or verify a successful build; if so, your commit will receive a
 +1. Other users may also give your commit +1. For a commit to be merged,
 it needs to receive a +2. **Note:** A +1 and a +1 does not make a +2.
 Only certain users can give a +2.

 ## Step 6 (optional): bash-git-prompt

 To help make it easier to understand the state of the git repository
 without running `git status` or `git log`, there is a way to make the
 command line show the status of the repository at every point. This
 is through bash-git-prompt.

 Instructions for installing this are found at:
 <https://github.com/magicmonty/bash-git-prompt>.
 **Note:** Feel free to search for different versions of git prompt,
 as this one is specific to bash.

 Alternatively, follow the instructions below:
 Run the following two commands in the command line:

 ```Bash
 cd
 git clone https://github.com/magicmonty/bash-git-prompt.git \
     .bash-git-prompt --depth=1
 ```
 **Note:** cd will change your directory to your home directory, so the
 git clone command will be run there.

 Finally, open the `~/.bashrc` file and append the following two lines:

     GIT_PROMPT_ONLY_IN_REPO=1
     source ~/.bash-git-prompt/gitprompt.sh

 Now, whenever you are in a git repository, it will continuously display
 its state.

 There also are additional configurations that you can change depending
 on your preferences. If you wish to do so, look at the "All configs for
 .bashrc" section on <https://github.com/magicmonty/bash-git-prompt>.
 Listed in that section are various lines that you can copy, uncomment
 and add to your .bashrc file to change the configurations. Example
 configurations include avoid fetching remote status, and supporting
 versions of Git older than 1.7.10.

 ## Appendix: Miscellaneous Advice

 ### Updating a commit after running git push:

 Suppose you would like to update a commit that has already been pushed
 to the remote repository. If the commit you wish to update is the most
 recent commit you have made, after making your desired changes, stage
 the files (either using git add or in git cola), and amend the commit.
 To do so, if you are using the command line, run `git commit --amend`.
 If you are using git cola, click on the gear icon located on the upper
 left side under **Commit** and select **Amend Last Commit** in the drop
 down menu. Then, stage the files you have changed, commit the changes,
 and run git push to push the changes to the remote repository. Your
 change should be reflected in Gerrit as a new patch set.

 If, however, the commit you wish to update is not the most recent commit
 you have made, you will first need to checkout that commit. To do so,
 find the URL of the commit on <https://review.coreboot.org> and go to
 that page; if the commit is one that you previously pushed, it can be
 found by selecting **My** and then **Changes** in the upper left corner.
 To checkout this commit, in the upper right corner, click on
 **Download**, and copy the command listed next to checkout by clicking
 **Copy to clipboard**. Then, run the copied command in your coreboot
 repository. Now, the last commit should be the most recent commit to
 that patch; to update it, make your desired changes, stage the files,
 then amend and push the commit using the instructions in the above
 paragraph.
	# Tutorial, part 2: Submitting a patch to coreboot.org

	## Step 1: Set up an account at coreboot.org

	If you already have an account, skip to Step 2.

	Otherwise, go to <https://review.coreboot.org> in your preferred web
	browser. Select Sign in in the upper right corner.

	Select the appropriate sign-in. For example, if you have a Google
	account, select Google OAuth2 (gerrit-oauth-provider plugin).
	Note: Your username for the account will be the username of the
	account you used to sign-in with. (ex. your Google username).

	## Step 2a: Set up SSH keys

	If you prefer to use an HTTP password instead, skip to Step 2b.

	If you do not have an SSH key set up on your account already (as is the
	case with a newly created account), follow the instructions below;
	otherwise, doing so could overwrite an existing key.

	In a terminal, run `ssh-keygen -t ed25519` and confirm the default path
	`.ssh/id_ed25519`.

	Make a passphrase -- remember this phrase. It will be needed whenever
	you use this public key. Note: You might want to use a short
	password, or forego the password altogether as you will be using it very
	often.

	Copy the content of `.ssh/id_ed25519.pub` (notice the ".pub" suffix
	as you need to send the public key) into the textbox "New SSH Key" at
	<https://review.coreboot.org/settings/#SSHKeys> and save it.

	## Step 2b: Set up an HTTP Password

	Alternatively, instead of using SSH keys, you can use an HTTP password.
	To do so, after you select your name and click on Settings on the
	left-hand side, rather than selecting SSH Public Keys, select **HTTP
	Password**.

	Click Generate Password. This should fill the "Password" box with a
	password. Copy the password, and add the following to your
	`$HOME/.netrc` file:

	machine review.coreboot.org login YourUserNameHere password YourPasswordHere

	where YourUserNameHere is your username, and YourPasswordHere is the
	password you just generated.

	If your system is behind a snooping HTTPS proxy, you might also have to
	make its SSL certificate known to curl, a system specific operation.
	If that's not possible for some reason, you can also disable SSL
	certificate verification in git:

	git config [--global] http.sslVerify [true\|false]

	The `--global` argument sets it for all git transfers of your local
	user, `false` means not to validate the certificate.

	If that still doesn't allow you to pull or push changes to the server,
	the proxy is likely tampering with the data stream, in which case
	there's nothing we can do.

	## Step 3: Clone coreboot and configure it for submitting patches

	On Gerrit, click on the Browse tab in the upper left corner and
	select Repositories. From the listing, select the "coreboot" repo.
	You may have to click the next page arrow at the bottom a few times to
	find it.

	If you are using SSH keys, select ssh from the tabs under "Project
	coreboot" and run the "clone with commit-msg hook" command that's
	provided. This should prompt you for your id_rsa passphrase, if you
	previously set one.

	Note: if the ssh option is not showing, check that you have a
	username set. Click the profile picture at the top right and select
	User Settings, then set your username in the Profile section.

	If you are using HTTP, instead, select http from the tabs under
	"Project coreboot" and run the command that appears.

	Now is a good time to configure your global git identity, if you haven't
	already.

	git config --global user.name "Your Name"
	git config --global user.email "Your Email"

	Finally, enter the local git repository and set up repository specific
	hooks and other configurations.

	cd coreboot
	make gitconfig

	## Step 4: Submit a commit

	An easy first commit to make is fixing existing checkpatch errors and
	warnings in the source files. To see errors that are already present,
	build the files in the repository by running `make lint` in the coreboot
	directory. Alternatively, if you want to run `make lint` on a specific
	directory, run:

	util/lint/lint-007-checkpatch <filepath>

	where `filepath` is the filepath of the directory (ex.
	`src/cpu/amd/car`).

	Any changes made to files under the src directory are made locally,
	and can be submitted for review.

	Once you finish making your desired changes, use the command line to
	stage and submit your changes. An alternative and potentially easier way
	to stage and submit commits is to use git cola, a graphical user
	interface for git. For instructions on how to do so, skip to Step 4b.

	## Step 4a: Use the command line to stage and submit a commit

	To use the command line to stage a commit, run

	git add <filename>

	where `filename` is the name of your file.

	To commit the change, run

	git commit -s

	Note: The -s adds a signed-off-by line by the committer. Your commit
	should be signed off with your name and email (i.e. Your Name
	\<Your Email\>, based on what you set with git config earlier).

	Running git commit first checks for any errors and warnings using lint.
	If there are any, you must go back and fix them before submitting your
	commit. You can do so by making the necessary changes, and then staging
	your commit again.

	When there are no errors or warnings, your default text editor will
	open. This is where you will write your commit message.

	The first line of your commit message is your commit summary. This is a
	brief one-line description of what you changed in the files using the
	template below:

	<filepath>: Short description

	For example,

	cpu/amd/pi/00630F01: Fix checkpatch warnings and errors

	Note: It is good practice to use present tense in your descriptions
	and do not punctuate your summary.

	Then hit Enter. The next paragraph should be a more in-depth explanation
	of the changes you've made to the files. Again, it is good practice to
	use present tense. Ex.

	Fix space prohibited between function name and open parenthesis,
	line over 80 characters, unnecessary braces for single statement
	blocks, space required before open brace errors and warnings.

	When you have finished writing your commit message, save and exit the
	text editor. You have finished committing your change. If, after
	submitting your commit, you wish to make changes to it, running `git
	commit --amend` allows you to take back your commit and amend it.

	When you are done with your commit, run `git push` to push your commit
	to coreboot.org. Note: To submit as a private patch, use `git push
	origin HEAD:refs/for/main%private`. Submitting as a private patch
	means that your commit will be on review.coreboot.org, but is only
	visible to yourself and those you add as reviewers. This mode isn't
	perfect: Somebody who knows the commit ID can still fetch the change and
	everything it refers (e.g. parent commits).

	This has been a quick primer on how to submit a change to Gerrit for
	review using git. You may wish to review the [Gerrit code review
	workflow
	documentation](https://gerrit-review.googlesource.com/Documentation/intro-user.html#code-review),
	especially if you plan to work on multiple changes at the same time.

	## Step 4b: Use git cola to stage and submit a commit

	If git cola is not installed on your machine, see
	<https://git-cola.github.io/downloads.html> for download instructions.

	After making some edits to src files, rather than run `git add`, run
	`git cola` from the command line. You should see all of the files
	edited under "Modified".

	In the textbox labeled "Commit summary" provide a brief one-line
	description of what you changed in the files according to the template
	below:

	<filepath>: Short description

	For example,

	cpu/amd/pi/00630F01: Fix checkpatch warnings and errors

	Note: It is good practice to use present tense in your descriptions
	and do not punctuate your short description.

	In the larger text box labeled 'Extended description...' provide a more
	in-depth explanation of the changes you've made to the files. Again, it
	is good practice to use present tense. Ex.

	Fix space prohibited between function name and open parenthesis,
	line over 80 characters, unnecessary braces for single statement
	blocks, space required before open brace errors and warnings.

	Then press Enter two times to move the cursor to below your description.
	To the left of the text boxes, there is an icon with an downward arrow.
	Press the arrow and select "Sign Off." Make sure that you are signing
	off with your name and email (i.e. Your Name \<Your Email\>,
	based on what you set with git config earlier).

	Now, review each of your changes and mark either individual changes or
	an entire file as Ready to Commit by marking it as 'Staged'. To do
	this, select one file from the 'Modified' list. If you only want to
	submit particular changes from each file, then highlight the red and
	green lines for your changes, right click and select 'Stage Selected
	Lines'. Alternatively, if an entire file is ready to be committed, just
	double click on the file under 'Modified' and it will be marked as
	Staged.

	Once the descriptions are done and all the edits you would like to
	commit have been staged, press 'Commit' on the right of the text
	boxes.

	If the commit fails due to persisting errors, a text box will appear
	showing the errors. You can correct these errors within 'git cola' by
	right-clicking on the file in which the error occurred and selecting
	'Launch Diff Tool'. Make necessary corrections, close the Diff Tool and
	'Stage' the corrected file again. It might be necessary to refresh
	'git cola' in order for the file to be shown under 'Modified' again.
	Note: Be sure to add any other changes that haven't already been
	explained in the extended description.

	When ready, select 'Commit' again. Once all errors have been satisfied
	and the commit succeeds, move to the command line and run `git push`.

	## Step 5: Let others review your commit

	Your commits can now be seen on review.coreboot.org if you select "Your"
	and click on "Changes" and can be reviewed by others. Your code will
	first be reviewed by build bot (Jenkins), which will either give you a
	warning or verify a successful build; if so, your commit will receive a
	+1. Other users may also give your commit +1. For a commit to be merged,
	it needs to receive a +2. Note: A +1 and a +1 does not make a +2.
	Only certain users can give a +2.

	## Step 6 (optional): bash-git-prompt

	To help make it easier to understand the state of the git repository
	without running `git status` or `git log`, there is a way to make the
	command line show the status of the repository at every point. This
	is through bash-git-prompt.

	Instructions for installing this are found at:
	<https://github.com/magicmonty/bash-git-prompt>.
	Note: Feel free to search for different versions of git prompt,
	as this one is specific to bash.

	Alternatively, follow the instructions below:
	Run the following two commands in the command line:

	```Bash
	cd
	git clone https://github.com/magicmonty/bash-git-prompt.git \
	.bash-git-prompt --depth=1
	```
	Note: cd will change your directory to your home directory, so the
	git clone command will be run there.

	Finally, open the `~/.bashrc` file and append the following two lines:

	GIT_PROMPT_ONLY_IN_REPO=1
	source ~/.bash-git-prompt/gitprompt.sh

	Now, whenever you are in a git repository, it will continuously display
	its state.

	There also are additional configurations that you can change depending
	on your preferences. If you wish to do so, look at the "All configs for
	.bashrc" section on <https://github.com/magicmonty/bash-git-prompt>.
	Listed in that section are various lines that you can copy, uncomment
	and add to your .bashrc file to change the configurations. Example
	configurations include avoid fetching remote status, and supporting
	versions of Git older than 1.7.10.

	## Appendix: Miscellaneous Advice

	### Updating a commit after running git push:

	Suppose you would like to update a commit that has already been pushed
	to the remote repository. If the commit you wish to update is the most
	recent commit you have made, after making your desired changes, stage
	the files (either using git add or in git cola), and amend the commit.
	To do so, if you are using the command line, run `git commit --amend`.
	If you are using git cola, click on the gear icon located on the upper
	left side under Commit and select Amend Last Commit in the drop
	down menu. Then, stage the files you have changed, commit the changes,
	and run git push to push the changes to the remote repository. Your
	change should be reflected in Gerrit as a new patch set.

	If, however, the commit you wish to update is not the most recent commit
	you have made, you will first need to checkout that commit. To do so,
	find the URL of the commit on <https://review.coreboot.org> and go to
	that page; if the commit is one that you previously pushed, it can be
	found by selecting My and then Changes in the upper left corner.
	To checkout this commit, in the upper right corner, click on
	Download, and copy the command listed next to checkout by clicking
	Copy to clipboard. Then, run the copied command in your coreboot
	repository. Now, the last commit should be the most recent commit to
	that patch; to update it, make your desired changes, stage the files,
	then amend and push the commit using the instructions in the above
	paragraph.