The previously used splits between memory allocated for ROM code,
2nd stage bootloader and the app were somewhat safe and conservative.
This resulted in some space being unavailable for static allocation
in the app.
This commit increases the space available for static allocation to the
maximum possible amount.
1. Some of the ROM code static allocation is only used in UART/USB/SPI
download modes. This region ("shared buffers") has been placed at
the lower end of ROM memory area, to be reusable in flash boot
mode. The 2nd stage bootloader linker script is modified to "pack"
all sections exactly up to the end but with roughly 8K margin between
startup stacks.
2. Instead of calculating the sections placement and hardcoding the
addresses in the LD script again, rewrite it to calculate the
start address of each memory region automatically based on the
logic above.
3. Adjust the app memory layout (SRAM_IRAM_END) accordingly,
increasing the space available for static allocation.
Overall these changes increase the space available for static
allocation by about 78kB.
The downside of these changes is that the 2nd stage bootloader .data
segment is now directly adjacent to the startup stack on the PRO CPU.
Previously, there was effectively about 78kB of extra stack space for
the PRO CPU, before the stack would run into the data segment.
Add the possibility to have user bootloader components. This is performed
from an application/project, by creating bootloader components. To do so,
it is required to create a `bootloader_component` directory containing
the custom modules to be compiled with the bootloader.
Thanks to this, two solutions are available to override the bootloader now:
- Using hooks within a user bootloader component
- Using a user defined `main` bootloader component to totally override the
old implementation
Please check the two new examples in `examples/custom_bootloader`
* Closes https://github.com/espressif/esp-idf/issues/7043
The CPU might prefetch instructions, which means it in some cases
will try to fetch instruction located after the last instruction in
flash.text.
Add dummy bytes to ensure fetching these wont result in an error,
e.g. MMU exceptions
Summary of changes:
- bootloader_clock split into *_clock_init and *_clock_loader.
Only esp_clk_apb_freq is in *_clock_loader.
- bootloader_common moved out of loader; functions needed in loader
(or, referenced from bootloader_utility) were moved into
bootloader_common_loader.c.
- assert and abort moved into bootloader_panic, made part of the
loader
- rtc_clk and rtc_time made part of loader
Bootloader DRAM now ends at 0x3FFEAB00 which is the start of ROM
static RAM (reclaimable after app is running).
IRAM loader segment increased by 8KB.
Available total static RAM for the app is now reduced by 16KB.
This commit updates the watchdog timers (MWDT and RWDT)
in the following ways:
- Add seprate LL for MWDT and RWDT.
- Add a combined WDT HAL for all Watchdog Timers
- Update int_wdt.c and task_wdt.c to use WDT HAL
- Remove most dependencies on LL or direct register access
in other components. They will now use the WDT HAL
- Update use of watchdogs (including RTC WDT) in bootloader and
startup code to use the HAL layer.
Goal is that multiple faults would be required to bypass a boot-time signature check.
- Also strengthens some address range checks for safe app memory addresses
- Change pre-enable logic to also check the bootloader signature before enabling SBV2 on ESP32
Add some additional checks for invalid sections:
- Sections only partially in DRAM or IRAM are invalid
- If a section is in D/IRAM, allow the possibility only some is in D/IRAM
- Only pass sections that are entirely in the same type of RTC memory region
