 Dyna i fynd eu gweld i'r gweithio'r ddal, o'r ddal gweld i'r ddod. Ac mae'r ddod yn psychos y interim yn gyda'r gweithio. Rwy'n cyfrifio'n gwyaf yw'r yngrifo'r ddod y gwreithio'r ddod yma, o'r ddod y cwmlo'n gyfrifio'r ddod yn cyfrifio'r ddod yn cyfrifio'r ddod yn cyfrifio'r ddod yma. Mae'r obyledd yw'r ddod ytaf هو'r hanf جeefwyr A Fwyrwyr. Felly, wedi ydych chi'n bwysig y gwaith. Rwy'n gweithio'n gwasanaethau haf yw i'w gwasanaethau. Rwy'n gwneud y dyn nhw'n gwasanaethau u bwysig. Felly, thosegwch ei syl iawn i ddweud o wlad yn mynd ar fynd o'r домuu yng nghylch. Felly, os wrthyn ni'n byw ystod i ni'n gwaith yn gweithi gynorthfynol. E bent hwnnw, gorau ond yn y pethau yng nghylcheddon. Mae'n jwy'n gweithio'n gweithio ar gyfer rumiaid. Start GDB Debuggers in TFA and examples of modifications for secure peripheral assignments. So because of time constraints in our day we're only going up to running some standard U-boot commands and modifying something and then showing you the different U-boot configurations. But you've got the slides to carry on to see all the different functions that you have in this U-boot customisation section. Felly, we're going to stop the hands-on at slide number seven, the rest of the slide set will be for your information so that you can have a play-around later on. As with the previous lab, the color coding continues. So the yellow commands are for the host side, blue commands for your target side, and again the icons in the top left-hand corner, theory and practice are the same as you've seen from the previous example. Felly mae'n dweud eich clynyddiadion llunio o'r lŵs i ddechrau a ysgolwyr, mae'n hyn sy'n de chi'n mynd i'r wicci, yn cyfwyd â fardgo'r llunio ar hyn o ffraîg ddiw lle i'ch ddiwrs mae'n fwych EST.com, yn fally mae'n cael ei gwneud â chi dweud i'r wicci ac i arnyn nhw'r gwwt erbyn o'u bwysig o'r wicci. Mae yna'r ydych chi'n mynd i'n mynd i'w rhaid i phallu yng nghym逰 wedi'i gyda rydym yn gweithio'r lab gyda'r Lwyddon Minicom yn i badaeth nid, fel y mae hyn ar gyfer rydym yn gweithio'r lab gyda ll unexpected. Rhaedd hyn o'n meddwl eithaf ei ddechlig o lefydd. Ond rydyn ni'n fawr afwrdd Ohtoboot, rydyn ni'n meddwl ei wneud blaid o lefydd. Mae ydych chi'n modd 1-2 fan o gilydd, felly byddai yn gweithio'n gymhwyd. On hwnna, efallai yna fydd wedi'i dod i gweithio ar gyfer y nibwyr yw'r lwyddon eithaf, If I go back to my screen and make sure I'm active in the correct terminal window, this is my minicom window that was already open and if I go reboot or you can hit the black button as well on your target board and you have to get ready for this command. There we go. So I've managed to interrupt it at the right time where it says hit any key to stop autoboot and to prove them there I'll hit my carriage return to it three times. So I've managed to interrupt my boot sequence now so that we are in a partial configuration of U-boot. So now at the moment we only have U-boot standard commands. We don't have the full U-boot command set. So to see what commands we are we can hit the help key. So if we go into our terminal window and type help and it's fairly quick there but you can see all the different commands that we've got. So we don't have the full list of commands in here that you can now scroll up and see all the commands that we do have. So now we can go and have a look at our external memory map which is on our MMC. So if we go MMC part we can go and examine all the different partitions on our multimedia card. So there you can see we've got seven partitions. Scroll up there so you can see first stage boot loader partitions one and two, second stage boot loader and bootfs, rootfs, vendorfs as well as in there and userfs. And if we want to go and examine in detail one of these partitions we can see that we want to list with the file structure of extension two MMC partition number four. So this is what this command is going to give us. So if I go back in here, here XT, two LS, MMC, zero, four, so there you can now see what's in that particular partition and you can see our device tree blob there for our A7 and our M4 that's visible inside there and right at the top you can see the ETBs as well for the discovery kit ones, evaluation boards, things like that. So now we want to set the board to appear as a mass storage device for our host laptop. So rather than keep doing everything at the terminal window, we can set up our board to be a USB mass storage on our host side. This is where you'll need your second USB type C cable. So as soon as I type in this command here we will get a countdown here to say that I've got so long to reconnect my second USB cable and then my target board is then halted at that point. So if I go back into here, scroll back to the bottom again, so UMS, zero, C, zero. Please connect to USB cable so I need my second USB cable now, there we go. You can now see that all my partitions have come through. So we've got my bootfs partition, my rootfs partition, urfs partition and vendorfs partition have now all become visible inside the device. So now if I go into my host terminal window, I can list the blocks and I'll be able to see all my different partition blocks that are available to me and go back to my root again. If I go LSBLK, so there you can see all the different partition blocks that we've got inside and the sizes of each of these partitions that we have. So now we can actually do a mount of each of these partitions into the correct area and we can go and have a look at our bootfs. So if we follow each of these commands through individually, you can observe the different contents of different areas of the memory card. So eventually you'll see on the right-hand side my terminal window as I go through all these different commands. So I've now mounted all my drives, I'm now going to look specifically at bootfs, there you can see all the partition labels and now I can switch to the label bootfs and there we can see what's actually in our bootfs structure. So you can see there we've got all the different device tree blobs visible and you can see our splash screen. So it's the splash screen that we're going to have a look at. We now need to go and change the splash screen so we need to go to our lab directory and copy a new splash screen across and then synchronise. So we'll follow those commands through, I'm going to change directory to where our splash screen should be located, I'm now going to copy across the splash screen from our hands on to our target board so we're going to change the splash screen now. So it was the ST logo originally so now it'll be something different and just like before we have to do a sync to make sure everything gets refreshed in the system. And now because we don't have the full command set we need to first disconnect our connection so over here you can still see that we're connected here so I have to go back into this terminal window and break the connection of our drives so control C so that's now aborted the connection of the USB mass storage controller to the host and because we don't have the full command set of U-boot we have to type reset this time and that will now go and reset my target board and hopefully you should see that the splash screen has now changed on your target board as it's rebooting and I'm hoping you should all be able to see a squashed penguin now as your screen reboots. So that's as far as we go because that's a modification now of something in U-boot. Okay it's only the splash screen that we're modifying but it means you've actually modified something in U-boot. The slides now go on to show you lots more features of what you can do inside this lab or boot customisation part. You can go and view different environment variables so you can go and see the location of the splash screen. You can go and have a look at the kernel address. You can modify kernel command line information so you can have a look at that. You can go and edit the add-on board so you can play around with the configuration for this particular one is a mem shield so it's a mem's environment shield that you can plug in on the Arduino connectors on the bottom side of the board again to playing around with the information for the configuration for the mem shield. You can modify partition sizes in this section. This one might be of interest to you depending on what your application is boot time optimisation so you might want to be able to do boot time and change the speed at things boot up in the target system and all this information you can get from the wiki so there's a dedicated section on the wick on how to optimise the boot time so if you want to play around with the boot time then there's a dedicated link on the wiki for that. Then you go into the gdb debug for the tfa so you can have a play around with debugging the tfa. This one shows you how to open an OCD connection via the JTAG or your gdb debug and again this continues through different sections for the debugging side so again all the gdb commands are available on the wiki so you can get all the information about how to do the gdb debug commands through the wiki pages. Then you can set break points continue to the next break points have a look at the stack and finally exit the gdb and the last section here is the tfa configuring the peripheral assignments for the extended trust zone security so again we've got device tree configuration for the extended trust zone page on the wiki and it tells you how to configure it set up the firewall and possible areas that you want to protect inside the system so this bit showing you how to configure i2c number four to be a secure as default from the reference manual there and then it tells you how to do it set it into secure mode and u-boot would freeze while accessing the i2c four number clock so there's lots of information in these slides the most easiest one to show of modifying was the splash screen but once you're customizing u-boot and you've interrupted u-boot there is a lot you can do at this particular point