Modifying greenVIP

[HiddenSquid]

Hello,

I have already partially addressed a similar topic in another post, but was asked to get additional information in a new topic.

I am trying to use/modify the greenVIP demo to create a custom project.

Please correct me if I'm wrong at any point, as this is just what I have understood so far:

As I understand then, the boot sequence should be as follows:

1. When the bootCFG pins are at the correct position, then the bootROM chip starts executing code from address 0x0, which is the address for external flash.
2. At the address 0x0 is the IVT (Image Vector Table), which is a part of the BLOB, with the purpose of pointing to the DCD, the boot table and the defining the boot core.
   • In the S32 Design Studio IVT tool there is the option to load the DCD and the Application bootloader. What exactly is the application bootloader and why do I need to provide the application bootloader with a RAM start and entry pointers? Is it just another name for the boot table or where or how can I configure the boot table?
   • The IVT tool also has an option of "Export BLOB" and Export "IVT Image". What is the difference or what does a BLOB contain?
3. Then the DCD (Device Configuration Data) section runs, at 0x0000_0100, which is supposed to configure memory access and clocks for each core.
   • The S32 DS also has DCD tool, where I can add or edit the WRITE and CHECK commands. Do I understand correctly that it is for configuring peripheral registers? Can I actually initialize all registers with the DCD or how do I know which registers should be modified by the DCD and which can me modified during runtime?
   • Can or under which conditions should it be configured if I am trying to boot my own code?
4. Then the Boot Table runs, located at 0x0010_0000, with the purpose of loading all the cores code in to RAM. 
   • Please confirm this and as I already asked above, where can the boot table be configured?
5. Then basically all the cores are started.

Did I miss any important steps?

• Additionally, as I understand, one of the large benefits of greenVIP is to have a multicore boot up sequence that is deterministic and can be or already is verified for Automotive grade safety. Please confirm or correct me if I'm wrong? Does that also mean the code for the M33 boot core should not or can not be modified?
• Furthermore, if each cores binaries are just copied from FLASH to RAM during the boot sequence, is the intended way to use greenVIP architecture for custom projects, to just flash my own code binaries to the appropriate FLASH address as appointed by greenVIP User Guide Table 11. Flash address for each partition? So for example if I want to run code on RTU_0_C0, I flash my binaries to address 0x0024_0000?

[Joey_z]

Hi,HiddenSquid

Thank you for your question and detail information. 

I know you are trying to use/modify the greenVIP demo to create a custom project. So, you can refer to the S32ZE_GreenVIP_1.x.1/doc/UG_S32ZE_GreenVIP.pdf for your application.

The Bootloader application has been integrated for both flavors of GreenVIP (SMU_LA|SMU_LAV) on the S32Z2 device. BootROM acts as a stage 1 bootloader, loading the primary application (SMU_LA|SMU_LAV). Following this, Bootloader takes control in stage 2 to load secondary applications (such as RTU_0 cores, RTU_1 cores, FLEXLLCE and others).

GreenVIP booting in Service Mode for SMU_LA on S32Z2 device as the following picture.

1.When the bootCFG pins are at the correct position, then the bootROM chip starts executing code from address 0x0, which is the address for external flash.

>>>The BootROM does not directly "fetch instructions and execute" from the 0x0 location of the external Flash. After power-on, the chip first runs the BootROM in its internal ROM. Based on the settings in BootCFG/switches, it selects the boot medium (such as QSPI/SD/eMMC, etc.), and then reads the boot header/IVT on the boot medium to determine the subsequent actions.

2.At the address 0x0 is the IVT (Image Vector Table), which is a part of the BLOB, with the purpose of pointing to the DCD, the boot table and the defining the boot core.

In the S32 Design Studio IVT tool there is the option to load the DCD and the Application bootloader. What exactly is the application bootloader and why do I need to provide the application bootloader with a RAM start and entry pointers? Is it just another name for the boot table or where or how can I configure the boot table?

>>>The Application Bootloader is the first-stage application image. For S32Z/E + greenVIP, it is usually the boot management program on the SMU/M33 side. The BootROM will move it to RAM and jump to its entry point.

The IVT tool also has an option of "Export BLOB" and Export "IVT Image". What is the difference or what does a BLOB contain?

>>>The function of IVT is to serve as a "pointer table", instructing the BootROM where to retrieve the DCD , the application bootloader and other image blocks, used for being parsed by BootROM.
BLOB is based on the IVT, the relevant images are physically assembled into a single writable overall image (which can be directly written to the boot medium) according to memory/alignment.

3.Then the DCD (Device Configuration Data) section runs, at 0x0000_0100, which is supposed to configure memory access and clocks for each core.

The S32 DS also has DCD tool, where I can add or edit the WRITE and CHECK commands. Do I understand correctly that it is for configuring peripheral registers? Can I actually initialize all registers with the DCD or how do I know which registers should be modified by the DCD and which can me modified during runtime?

Can or under which conditions should it be configured if I am trying to boot my own code?

>>>The role of DCD is a set of "early initialization scripts for peripheral/storage subsystems" executed during the BootROM stage. It's typical functions include initializing SRAM/DDR, setting QSPI parameters, certain necessary clocks/reset, etc. so that the subsequent application image can be correctly transferred and executed. DCD aims to minimize the hardware conditions that must be prepared "after BootROM and before the application image", higher-level peripheral initialization (such as drivers, complex timing modules) should be done within the application bootloader/application.

4.Then the Boot Table runs, located at 0x0010_0000, with the purpose of loading all the cores code in to RAM. 

Please confirm this and as I already asked above, where can the boot table be configured?

>>>After the SMU is started by the BootROM, the Bootloader will load and/or start all the images for the RTUs, according to the Boot Table. You can refer to the 3.4 Compile the boot table of UG_S32ZE_GreenVIP.pdf to know more about the boot table configuration.

5.Additionally, as I understand, one of the large benefits of greenVIP is to have a multicore boot up sequence that is deterministic and can be or already is verified for Automotive grade safety. Please confirm or correct me if I'm wrong? Does that also mean the code for the M33 boot core should not or can not be modified?

>>>The GreenVIP (S32Z/E Vehicle Integration Platform) is intended to provide a functional software platform that allows customers to begin developing their applications on the S32Z/E family with minimal effort. It enables standalone development of each single application (vECU), and their integration. GreenVIP platform is aimed to demonstrate a proper use of S32Z/E benefitting from unique device features. For the application of M33 at the software level, the customer can make modifications. This is a software-level development application. The greenvip we provide is for customer reference and use, facilitating the customer's rapid development.

6.Furthermore, if each cores binaries are just copied from FLASH to RAM during the boot sequence, is the intended way to use greenVIP architecture for custom projects, to just flash my own code binaries to the appropriate FLASH address as appointed by greenVIP User Guide Table 11. Flash address for each partition? So for example if I want to run code on RTU_0_C0, I flash my binaries to address 0x0024_0000?

>>>For the GreenVIP application, if you flash your binaries to address 0x0024_0000, as you flash your RTU_0_C0.bin to this address, the SMU Bootloader will automatically copy it to the RAM. However, it can only be started if the entry/start address is the same.

Hope this information can help you.

BR

Joey

[HiddenSquid]

Hey @Joey_z ,

Thank you for the answer, this helps to understand a lot conceptually, but leaves me hanging a bit from the practical perspective.

1. Regarding the boottable: section 3.4 Compile the boot table of UG_S32ZE_GreenVIP.pdf seems to only specify the compile process of the boot table, but not the actual configuration part. The same section also talks about bootloader configuration, but only from a Tresos project perspective. Is there an equal configuration tool for the S32 Design Studio or how should I approach this issue?
2. When you say "BLOB is based on the IVT", does that mean that the IVT is a part of the BLOB or is the compile process of the BLOB just based on the IVT? As I understand at the moment, then  the BLOB contains:
   1. The IVT
   2. The DCD
   3. The application bootloader
   I made the assumption based on the visual implication of the S32 DS IVT Tool. Please confirm or correct me.
3. Regarding the comment about greenVIP: "It enables standalone development of each single application (vECU), and their integration... The greenvip we provide is for customer reference and use, facilitating the customer's rapid development.". Could you elaborate on that more from a practical point of view, as to how could I approach developing my own software for the R52 cores and the M33/SMU core. For example, I found the main.c (added as attachment) file of the SMU_LA project, but it is again only implemented as a Tresos project and I can see the main function

int main(void)
{
  SwPartId = PART_ID;

  /* Monitoring initialization (SwPartId, osTaskID_First, osTaskID_Last, osTaskID_Reset) */
  Monitoring_Init(SwPartId, OsTaskASW_1ms, OsTaskASW_1000ms, OsTaskASW_1000ms);

  EcuM_Init(); /* start OS never returns */

  return 0;
}

But the I can't find the definition/contents of the EcuM_Init(), so it turns in to a dead end. Where exactly does it lead or where can I find the multicore boot process architecture description?

Thank you already in advance for taking the time!

[Joey_z]

Hi，HiddenSquid

Thank you for your reply and information.

1.Is there an equal configuration tool for the S32 Design Studio or how should I approach this issue?

>>>Please refer to the chapter  of 5.12 Boot Service. The boot service (Bootloader) is presented as a configurable component in the SMU tresos project. This component allows the configuration of multiple execution environments, application sources and application
image fragements. For the GreenVIP package, you only can use the Tresos for the Bootloader application.

2.When you say "BLOB is based on the IVT", does that mean that the IVT is a part of the BLOB or is the compile process of the BLOB just based on the IVT?

>>>The IVT/DCD/Application Bootloader are included in the BLOB.

3.But the I can't find the definition/contents of the EcuM_Init(), so it turns in to a dead end. Where exactly does it lead or where can I find the multicore boot process architecture description?

>>>For the GreenVIP, please try to load the Bootloader application to generate code in Tresos, then find the EcuM_Init() information. The GreenVIP package is a multicore, you also can try to refer to it.

BR

Joey