When ESP32-C2 is paired with a 26 MHz XTAL, the systimer tick
frequency becomes equal to 26 / 2.5 = 10.4 MHz. Previously we always
assumed that systimer tick frequency is integer (and 1 MHz * power of
two, above that!).
This commit introduces a new LL macro, SYSTIMER_LL_TICKS_PER_US_DIV.
It should be set in such a way that:
1. SYSTIMER_LL_TICKS_PER_US / SYSTIMER_LL_TICKS_PER_US_DIV equals the
actual systimer tick frequency,
2. and SYSTIMER_LL_TICKS_PER_US is integer.
For ESP32-C2 this means that SYSTIMER_LL_TICKS_PER_US = 52 and
SYSTIMER_LL_TICKS_PER_US_DIV = 5.
This introduced two possible issues:
1. Overflow when multiplying systimer counter by 5
- Should not be an issue, since systimer counter is 52-bit, so
counter * 5 is no more than 55-bit.
2. The code needs to perform:
- divide by 5: when converting from microseconds to ticks
- divide by 52: when converting from ticks to microseconds
The latter potentially introduces a performance issue for the
esp_timer_get_time function.
This commit updates the esp_cpu.h API. The new API presents a new
abstraction of the CPU where CPU presents the following interfaces:
- CPU Control (to stall/unstall/reset the CPU)
- CPU Registers (to read registers commonly used in SW such as SP, PC)
- CPU Interrupts (to inquire/allocate/control the CPUs 32 interrupts)
- Memory Port (to configure the CPU's memory bus for memory protection)
- Debugging (to configure/control the CPU's debugging port)
Note: Also added FORCE_INLINE_ATTR to the DoxyFile in order to pass doc
builds for esp_cpu.h
introduced in e44ead5356
1. The int8M power domain config by default is PD. While LEDC is using
RTC8M as clock source, this power domain will be kept on.
But when 8MD256 is used as RTC clock source, the power domain should
also be kept on.
On ESP32, there was protection for it, but broken by commit
e44ead5356. Currently the power domain
will be forced on when LEDC is using RTC8M as clock source &&
!int8m_pd_en (user enable ESP_PDP_DOMAIN_RTC8M in lightsleep). Otherwise
the power domain will be powered off, regardless of RTC clock source.
In other words, int8M domain will be forced off (even when 8MD256
used as RTC clock source) if LEDC not using RTC8M as clock source, user
doesn't enable ESP_PDP_DOMAIN_RTC8M, or in deep sleep.
On later chips, there's no such protection, so 8MD256 could't be used as
RTC clock source in sleep modes.
This commit adds protection of 8MD256 clock to other chips. Fixes the
incorrect protection logic overriding on ESP32. Now the power domain
will be determiend by the logic below (order by priority):
1. When RTC clock source uses 8MD256, power up
2. When LEDC uses RTC8M clock source, power up
3. In deepsleep, power down
4. Otherwise determined by user config of ESP_PDP_DOMAIN_RTC8M,
power down by default. (This is preferred to have highest
priority, but it's kept as is because of current code structure.)
2. Before, after the macro `RTC_SLEEP_CONFIG_DEFAULT` decides dbias, the
protection above may force the int8m PU. This may cause the inconsistent
of dbias and the int8m PU status.
This commit lifts the logic of pd int8m/xtal fpu logic to upper layer
(sleep_modes.c).
Related: https://github.com/espressif/esp-idf/issues/8007, https://github.com/espressif/esp-idf/pull/8089
temp
The legacy driver can't handle the breaking change between esp chips
very well.
And it's not elegant to extend new feature like DMA, ETM.
The new driver can return a opaque handle for each RMT channel.
An obvious transaction concept was also introduced.
TX and RX functionalities are splited out.
- Security features covers "secure boot", "flash encryption" etc.
- ECO revision specific modifications still need to be handled
through kconfig itself, as soc_caps.h is processed before ECO revision
selection
- This will simplify addition of security features for newer chips by
using these SOC capability macros
morris