hw/riscv: add SpacemiT K3 Pico-ITX machine

.github/workflows/build.yml

@@ -77,7 +77,7 @@ jobs:
           podman run --pull newer --init --rm -it -v $(pwd):$(pwd)
           -w $(pwd)/tests/docker/
           docker.io/pboqemu/qemu-ci:${{matrix.container}}
-          env QEMU_SRC=$(pwd) QEMU_WERROR="${{ env.QEMU_WERROR }}" ENABLE_RUST=0 INSTALL_DIR=/ BUILD_DIR=/tmp MAKEFLAGS="-j $(nproc)"
+          env QEMU_SRC=$(pwd) QEMU_WERROR="${{ env.QEMU_WERROR }}" ENABLE_RUST=0 EXTRA_CONFIGURE_OPTS=--disable-docs INSTALL_DIR=/ BUILD_DIR=/tmp MAKEFLAGS="-j $(nproc)"
           ./test-build
 
   build:

MAINTAINERS

@@ -1814,6 +1814,20 @@ F: include/hw/watchdog/k230_wdt.h
 F: tests/qtest/k230-sysctl-test.c
 F: tests/qtest/k230-wdt-test.c
 
+SpacemiT K3 Pico-ITX
+M: Chao Liu <[email protected]>
+L: [email protected]
+S: Maintained
+F: docs/system/riscv/spacemit-k3.rst
+F: hw/misc/spacemit-k3.c
+F: hw/riscv/spacemit-k3.c
+F: hw/sd/spacemit-k3-sdhci.c
+F: include/hw/misc/spacemit-k3.h
+F: include/hw/riscv/spacemit-k3.h
+F: include/hw/sd/spacemit-k3-sdhci.h
+F: tests/functional/riscv64/test_spacemit_k3.py
+F: tests/qtest/spacemit-k3-test.c
+
 Milk-V Duo
 M: Kuan-Wei Chiu <[email protected]>
 S: Maintained

README.md

@@ -12,6 +12,7 @@ for new machine requests or bug reports.
 | arch | machine | direct | firmware | src |
 | --- | --- | --- | --- | --- |
 | RISC-V | [`k230-canmv`](docs/system/riscv/k230-canmv.rst) | ✅ | ✅ | PM |
+| RISC-V | [`k3-pico-itx`](docs/system/riscv/spacemit-k3.rst) | ✅ | ✅ | PM |
 | RISC-V | [`milkv-duo`](docs/system/riscv/milkv-duo.rst) | ✅ | ✅ | UP |
 | RISC-V | [`riscv-server-ref`](docs/system/riscv/riscv-server-ref.rst) | ✅ | ✅ | UP |
 | ARM | [`phytium-pi`](docs/system/arm/phytium-pi.rst) | ✅ | ✅ | PM |

accel/tcg/user-exec.c

@@ -238,13 +238,16 @@ void page_dump(FILE *f)
 
 int page_get_flags(vaddr address)
 {
-    PageFlagsNode *p = pageflags_find(address, address);
+    PageFlagsNode *p;
+
+    RCU_READ_LOCK_GUARD();
 
     /*
      * See util/interval-tree.c re lockless lookups: no false positives but
      * there are false negatives.  If we find nothing, retry with the mmap
      * lock acquired.
      */
+    p = pageflags_find(address, address);
     if (p) {
         return p->flags;
     }
@@ -300,15 +303,15 @@ static void pageflags_create_merge(vaddr start, vaddr last, int flags)
 
     if (prev) {
         if (next) {
-            prev->itree.last = next->itree.last;
+            pageflags_create(prev->itree.start, next->itree.last, flags);
             g_free_rcu(next, rcu);
         } else {
-            prev->itree.last = last;
+            pageflags_create(prev->itree.start, last, flags);
         }
-        interval_tree_insert(&prev->itree, &pageflags_root);
+        g_free_rcu(prev, rcu);
     } else if (next) {
-        next->itree.start = start;
-        interval_tree_insert(&next->itree, &pageflags_root);
+        pageflags_create(start, next->itree.last, flags);
+        g_free_rcu(next, rcu);
     } else {
         pageflags_create(start, last, flags);
     }
@@ -370,8 +373,8 @@ static bool pageflags_set_clear(vaddr start, vaddr last,
     if (set_flags != merge_flags) {
         if (p_start < start) {
             interval_tree_remove(&p->itree, &pageflags_root);
-            p->itree.last = start - 1;
-            interval_tree_insert(&p->itree, &pageflags_root);
+            pageflags_create(p_start, start - 1, p_flags);
+            g_free_rcu(p, rcu);
 
             if (last < p_last) {
                 if (merge_flags & PAGE_VALID) {
@@ -393,11 +396,11 @@ static bool pageflags_set_clear(vaddr start, vaddr last,
             }
             if (last < p_last) {
                 interval_tree_remove(&p->itree, &pageflags_root);
-                p->itree.start = last + 1;
-                interval_tree_insert(&p->itree, &pageflags_root);
+                pageflags_create(last + 1, p_last, p_flags);
                 if (merge_flags & PAGE_VALID) {
                     pageflags_create(start, last, merge_flags);
                 }
+                g_free_rcu(p, rcu);
             } else {
                 if (merge_flags & PAGE_VALID) {
                     p->flags = merge_flags;
@@ -418,8 +421,8 @@ static bool pageflags_set_clear(vaddr start, vaddr last,
     if (set_flags == p_flags) {
         if (start < p_start) {
             interval_tree_remove(&p->itree, &pageflags_root);
-            p->itree.start = start;
-            interval_tree_insert(&p->itree, &pageflags_root);
+            pageflags_create(start, p_last, p_flags);
+            g_free_rcu(p, rcu);
         }
         if (p_last < last) {
             start = p_last + 1;
@@ -431,8 +434,8 @@ static bool pageflags_set_clear(vaddr start, vaddr last,
     /* Maybe split out head and/or tail ranges with the original flags. */
     interval_tree_remove(&p->itree, &pageflags_root);
     if (p_start < start) {
-        p->itree.last = start - 1;
-        interval_tree_insert(&p->itree, &pageflags_root);
+        pageflags_create(p_start, start - 1, p_flags);
+        g_free_rcu(p, rcu);
 
         if (p_last < last) {
             goto restart;
@@ -441,8 +444,8 @@ static bool pageflags_set_clear(vaddr start, vaddr last,
             pageflags_create(last + 1, p_last, p_flags);
         }
     } else if (last < p_last) {
-        p->itree.start = last + 1;
-        interval_tree_insert(&p->itree, &pageflags_root);
+        pageflags_create(last + 1, p_last, p_flags);
+        g_free_rcu(p, rcu);
     } else {
         g_free_rcu(p, rcu);
         goto restart;
@@ -504,6 +507,8 @@ bool page_check_range(vaddr start, vaddr len, int flags)
         return false; /* wrap around */
     }
 
+    RCU_READ_LOCK_GUARD();
+
     locked = have_mmap_lock();
     while (true) {
         PageFlagsNode *p = pageflags_find(start, last);

configs/devices/riscv64-softmmu/default.mak

@@ -10,6 +10,7 @@
 # CONFIG_SIFIVE_U=n
 # CONFIG_RISCV_VIRT=n
 # CONFIG_RISCV_SERVER_PLATFORM_REF=n
+# CONFIG_SPACEMIT_K3=n
 # CONFIG_MICROCHIP_PFSOC=n
 # CONFIG_SHAKTI_C=n
 # CONFIG_K230=n

docs/system/riscv/spacemit-k3.rst

@@ -0,0 +1,95 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+SpacemiT K3 Pico-ITX board (``k3-pico-itx``)
+================================================
+
+The ``k3-pico-itx`` machine models the standard RISC-V platform subset
+needed to boot a SpacemiT K3 SDK Linux kernel directly or through U-Boot on
+the K3 Pico-ITX board.  It focuses on the eight X100 application harts and
+does not expose the K3 A100 or IME harts.
+
+The machine has a fixed CPU topology and memory layout matching the Linux
+view of the board.  The default configuration must be used without overriding
+the CPU type, RAM size, or SMP topology.
+
+Supported devices
+-----------------
+
+The ``k3-pico-itx`` machine supports:
+
+* eight SpacemiT X100 harts implementing RVA23S64 in two clusters of four;
+* 256-bit RISC-V vector registers, Sstc, and the Smaia/Ssaia extensions;
+* 2 GiB of RAM starting at ``0x102000000``;
+* a 32 MiB firmware window starting at ``0x100000000``;
+* an ACLINT software interrupt and machine timer block with a 24 MHz timebase;
+* machine- and supervisor-level APLIC and IMSIC interrupt controllers;
+* the 8250-compatible UART0 at ``0xd4017000``, using interrupt source 42; and
+* the K3 SDHCI controller at ``0xd4280000``, using interrupt source 99.
+
+Boot options
+------------
+
+Both supported Linux boot paths start generic OpenSBI directly.  QEMU can
+either load Linux and its initramfs, or load U-Boot proper and let U-Boot load
+Linux from an SD image.  An external device tree is required because the
+machine validates the exact K3 topology and address map before boot.
+
+The following examples use artifacts built from the SpacemiT K3 Buildroot SDK
+v1.0.2 and published in the ``sdk-v1.0.2-qemu2`` release of
+``spacemit-k3-qemu-images``.
+
+Direct Linux boot
+~~~~~~~~~~~~~~~~~
+
+.. code-block:: bash
+
+   $ qemu-system-riscv64 \
+       -machine k3-pico-itx \
+       -bios fw_dynamic.bin \
+       -kernel Image \
+       -initrd k3-qemu-initramfs.cpio.gz \
+       -dtb k3-pico-itx-qemu.dtb \
+       -append "earlycon=uart8250,mmio32,0xd4017000,115200 \
+                console=ttyS0,115200 rdinit=/init" \
+       -nographic -no-reboot
+
+The machine supplies the fixed 2 GiB RAM size and 8-hart topology, so no
+``-m`` or ``-smp`` options are needed.  Direct kernel boot requires
+OpenSBI; ``-bios none`` is rejected when ``-kernel`` is present.
+The machine uses the fixed ``spacemit-x100`` CPU model.
+
+U-Boot and SD boot
+~~~~~~~~~~~~~~~~~~
+
+Decompress ``k3-qemu-sd.raw.xz``, then start U-Boot proper as OpenSBI's next
+stage:
+
+.. code-block:: bash
+
+   $ xz -dk k3-qemu-sd.raw.xz
+   $ qemu-system-riscv64 \
+       -machine k3-pico-itx \
+       -bios fw_dynamic.bin \
+       -kernel u-boot.bin \
+       -dtb k3-pico-itx-qemu-uboot.dtb \
+       -drive file=k3-qemu-sd.raw,if=sd,format=raw,snapshot=on \
+       -nographic -no-reboot
+
+U-Boot imports its deterministic environment from the SD boot partition and
+loads the Linux kernel, Linux device tree, and initramfs from that partition.
+The successful path prints ``K3-QEMU: Starting kernel from SD`` before Linux
+prints ``K3_LINUX_MVP_PASS``.
+
+Limitations
+-----------
+
+This machine is a Linux boot subset rather than a complete K3 hardware model.
+It disables the X100 H extension because the VS interrupt files and
+virtualization path are not modeled.  The A100 and IME harts, PCIe,
+networking, multimedia accelerators, power management, and most board
+peripherals are not implemented.
+
+The K3 BootROM, bootinfo parser, U-Boot SPL, and LPDDR training are not
+modeled.  QEMU provides initialized RAM and starts generic OpenSBI directly;
+the firmware boot path therefore uses U-Boot proper rather than the vendor
+SPL chain.

docs/system/target-riscv.rst

@@ -73,6 +73,7 @@ undocumented; you can get a complete list by running
    riscv/mips
    riscv/shakti-c
    riscv/sifive_u
+   riscv/spacemit-k3
    riscv/virt
    riscv/xiangshan-kunminghu
    riscv/riscv-server-ref

hw/misc/Kconfig

@@ -208,6 +208,9 @@ config RK3588_CRU
 config RK3588_SCMI
     bool
 
+config SPACEMIT_K3_CTRL
+    bool
+
 config MAC_VIA
     bool
     select MOS6522

hw/misc/meson.build

@@ -183,6 +183,7 @@ system_ss.add(when: 'CONFIG_MAC_VIA', if_true: files('mac_via.c'))
 
 system_ss.add(when: 'CONFIG_RK3588_CRU', if_true: files('rk3588_cru.c'))
 system_ss.add(when: 'CONFIG_RK3588_SCMI', if_true: files('rk3588_scmi.c'))
+system_ss.add(when: 'CONFIG_SPACEMIT_K3_CTRL', if_true: files('spacemit-k3.c'))
 system_ss.add(when: 'CONFIG_NXP_S32_MC_ME', if_true: files('nxp_s32_mc_me.c'))
 
 specific_ss.add(when: 'CONFIG_MIPS_CPS', if_true: files('mips_cmgcr.c', 'mips_cpc.c'))