WIP: add initial support for ESP32-S3

[denysvitali]

These are the first steps towards fixing #3442.

At the moment, the following TinyGo program doesn't print anything to stdout, but at least it seems like the main is reached:

package main

import "machine"

func main() {
	machine.InitSerial()

	for {
		machine.Serial.Write([]byte("Hello world :)\r\n"))
	}
}

Here is the full boot log:

ESP-ROM:esp32s3-20210327
Build:Mar 27 2021
rst:0x1 (POWERON),boot:0x9 (SPI_FAST_FLASH_BOOT)
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd0108,len:0x1710
load:0x403b6000,len:0x8c8
load:0x403ba000,len:0x2eb4
SHA-256 comparison failed:
Calculated: 94284163cda84609f6d502e80255fb42297565c0c3c1795798a0c2beda02fced
Expected: ab492d70a98095a7841c7bfbf1d6d0b6161e082227abfb2028c51ce7cbe6144a
Attempting to boot anyway...
entry 0x403b61c0
I (43) boot: ESP-IDF v4.4-dev-3540-g4e03a9c34c 2nd stage bootloader
I (43) boot: compile time 09:24:35
I (44) boot: chip revision: 0
I (47) boot.esp32s3: Boot SPI Speed : 80MHz
I (51) boot.esp32s3: SPI Mode       : DIO
I (56) boot.esp32s3: SPI Flash Size : 8MB
I (61) boot: Enabling RNG early entropy source...
W (66) bootloader_random: RNG for ESP32-S3 not currently supported
I (73) boot: Partition Table:
I (77) boot: ## Label            Usage          Type ST Offset   Length
I (84) boot:  0 nvs              WiFi data        01 02 00009000 00006000
I (91) boot:  1 phy_init         RF data          01 01 0000f000 00001000
I (99) boot:  2 factory          factory app      00 00 00010000 007f0000
I (106) boot: End of partition table
I (111) esp_image: segment 0: paddr=00010020 vaddr=3fc89000 size=00088h (   136) load
I (119) esp_image: segment 1: paddr=000100b0 vaddr=40370000 size=009dch (  2524) load
I (129) boot: Loaded app from partition at offset 0x10000
I (134) boot: Disabling RNG early entropy source...
W (139) bootloader_random: RNG for ESP32-S3 not currently supported

I have based my changes on v0.29.0, because I can't run Tinygo with Xtensa and LLVM 16. For whatever reason I get some errors while running tinygo build when the target is esp32 (or like in my case esp32s3):

unknown tool: -o
failed to run tool: clang

Much of my work here is copy & paste from the ESP32 code base, with a few adaptations. Hopefully it's a good start for someone else to continue my work :)

[denysvitali]

FYI, the chip sort of works now (I get UART outputs with a simple Go program) :)

[denysvitali]

FYI: I talked about the experience of porting TinyGo to the ESP32-S3 today at the Go Meetup @ AWS.
You can find the resources here.

[deadprogram]

Hello @denysvitali just looking at this PR thanks for working on it.

There have been several changes since it was first created, including that we are now using the official versions of the SVD files in the submodule. You perhaps no longer need that file?

Another suggestion would be to put the .S file into the targets directory instead of device/esp since generally those device directories are only used for generated file.

Hopefully you have some time to make some of these changes, as it would be great to get this into the next version of TinyGo.

Thank you!

[aykevl]

Generally looks good to me, just one extra test that's needed and a few code cleanliness comments.
Can you rebase this PR on top of the current dev branch, so we can see how well it works there?

[aykevl]

This file is exactly identical to src/device/esp/esp32.S, can you reuse that file but adjust this #define using a preprocessor macro? Something like:

#ifdef ESP32S3
#define PS_OWB_MASK                0x00000F01
#else
#define PS_OWB_MASK                0x00000F00
#endif

And then you can add it as a define in the "cflags" key in esp32s3.json ("-DESP32S3").

[aykevl]

Suggestion: replace this with a TODO instead. There's not much to be gained from having this commented code here: the same code is already present in the runtime support for the esp32c3.

[aykevl]

Please add the esp32s3 to the list in builder/builder_test.go to ensure this list is correct.