[docker] add document to docker container

Signed-off-by: Avimitin <[email protected]>

nix/t1/release/docker-image.nix

@@ -122,6 +122,8 @@ dockerTools.streamLayeredImage {
     mkdir -p /workspace/share
     cp ${../../../tests/t1.ld} /workspace/share/t1.ld
     cp ${../../../tests/t1_main.S} /workspace/share/main.S
+
+    cp ${./docker.md} /workspace/readme.md
   '';
 
   config = {

nix/t1/release/docker.md

@@ -0,0 +1,64 @@
+# Using the Emulator with Docker
+The emulator environment provides a set of tools and examples to help users get
+started. Below are detailed instructions and explanations for compiling and
+running test cases.
+
+## Examples
+There are four sample source code files located in the /workspace/examples
+directory. The T1 runtime stubs are placed under /workspace/share.
+
+This Docker container includes a Clang wrapper that simplifies the compilation
+process by handling most compiler options. Users can easily compile the example
+source code using the following commands:
+
+```bash
+cd /workspace/intrinsic.linear_normalization
+t1-cc -T /workspace/share/t1.ld /workspace/share/main.S linear_normalization.c -o linear_normalization.elf
+t1emu-verilated-simulator +t1_elf_file=linear_normalization.elf
+```
+
+## Marking Memory Regions
+The t1.ld file specifies how the linker organizes the memory layout. We use the following memory configurations:
+
+* Scalar memory: Starts at 0x20000000 with a size of 512MB.
+* Vector memory: Starts at 0x60000000 with a size of 1024MB.
+
+Developers can use the __attribute((section(".vbss"))) attribute to mark
+regions of memory that need to be copied to SRAM. For example, in
+linear_normalization.c:
+
+```c
+#define ARRAY_ZIZE 1024
+__attribute((section(".vbss"))) float actual[ARRAY_ZIZE];
+```
+
+## Main Function
+The main.S file acts as the main function. It initializes all registers before
+running a test case and then jumps to the test symbol. Developers writing new
+test cases should use the following structure for their entry point:
+
+```c
+int test() {
+    // Test implementation
+}
+```
+
+## Clang Wrapper
+The `t1-cc` command wraps several Clang options for convenience:
+
+```bash
+riscv32-none-elf-clang \
+    -I/path/to/t1-runtime/include -L/path/to/t1-runtime/lib \
+    -mabi=ilp32f -march=rv32gc_zvl2048b_zve32f -mno-relax -static -mcmodel=medany \
+    -fvisibility=hidden -fno-PIC -g -O3 -frandom-seed=<random string>
+```
+
+## Simulator Variants
+The simulator binary may differ based on the container used:
+
+* Containers with the suffix t1rocketemu include the t1rocketemu-verilated-simulator, which uses the Rocket core.
+* Containers with the suffix t1emu include the t1emu-verilated-simulator, which handles scalar instructions using Spike.
+
+Note: MMIO (Memory-Mapped I/O) support is currently unavailable in containers
+suffixed with -t1emu. Consequently, features like printf or framebuffer will
+not work in these containers.