1Xilinx Versal Virt (``xlnx-versal-virt``)
2=========================================
3
4Xilinx Versal is a family of heterogeneous multi-core SoCs
5(System on Chip) that combine traditional hardened CPUs and I/O
6peripherals in a Processing System (PS) with runtime programmable
7FPGA logic (PL) and an Artificial Intelligence Engine (AIE).
8
9More details here:
10https://www.xilinx.com/products/silicon-devices/acap/versal.html
11
12The family of Versal SoCs share a single architecture but come in
13different parts with different speed grades, amounts of PL and
14other differences.
15
16The Xilinx Versal Virt board in QEMU is a model of a virtual board
17(does not exist in reality) with a virtual Versal SoC without I/O
18limitations. Currently, we support the following cores and devices:
19
20Implemented CPU cores:
21
22- 2 ACPUs (ARM Cortex-A72)
23
24Implemented devices:
25
26- Interrupt controller (ARM GICv3)
27- 2 UARTs (ARM PL011)
28- An RTC (Versal built-in)
29- 2 GEMs (Cadence MACB Ethernet MACs)
30- 8 ADMA (Xilinx zDMA) channels
31- 2 SD Controllers
32- OCM (256KB of On Chip Memory)
33- XRAM (4MB of on chip Accelerator RAM)
34- DDR memory
35
36QEMU does not yet model any other devices, including the PL and the AI Engine.
37
38Other differences between the hardware and the QEMU model:
39
40- QEMU allows the amount of DDR memory provided to be specified with the
41  ``-m`` argument. If a DTB is provided on the command line then QEMU will
42  edit it to include suitable entries describing the Versal DDR memory ranges.
43
44- QEMU provides 8 virtio-mmio virtio transports; these start at
45  address ``0xa0000000`` and have IRQs from 111 and upwards.
46
47Running
48"""""""
49If the user provides an Operating System to be loaded, we expect users
50to use the ``-kernel`` command line option.
51
52Users can load firmware or boot-loaders with the ``-device loader`` options.
53
54When loading an OS, QEMU generates a DTB and selects an appropriate address
55where it gets loaded. This DTB will be passed to the kernel in register x0.
56
57If there's no ``-kernel`` option, we generate a DTB and place it at 0x1000
58for boot-loaders or firmware to pick it up.
59
60If users want to provide their own DTB, they can use the ``-dtb`` option.
61These DTBs will have their memory nodes modified to match QEMU's
62selected ram_size option before they get passed to the kernel or FW.
63
64When loading an OS, we turn on QEMU's PSCI implementation with SMC
65as the PSCI conduit. When there's no ``-kernel`` option, we assume the user
66provides EL3 firmware to handle PSCI.
67
68A few examples:
69
70Direct Linux boot of a generic ARM64 upstream Linux kernel:
71
72.. code-block:: bash
73
74  $ qemu-system-aarch64 -M xlnx-versal-virt -m 2G \
75      -serial mon:stdio -display none \
76      -kernel arch/arm64/boot/Image \
77      -nic user -nic user \
78      -device virtio-rng-device,bus=virtio-mmio-bus.0 \
79      -drive if=none,index=0,file=hd0.qcow2,id=hd0,snapshot \
80      -drive file=qemu_sd.qcow2,if=sd,index=0,snapshot \
81      -device virtio-blk-device,drive=hd0 -append root=/dev/vda
82
83Direct Linux boot of PetaLinux 2019.2:
84
85.. code-block:: bash
86
87  $ qemu-system-aarch64  -M xlnx-versal-virt -m 2G \
88      -serial mon:stdio -display none \
89      -kernel petalinux-v2019.2/Image \
90      -append "rdinit=/sbin/init console=ttyAMA0,115200n8 earlycon=pl011,mmio,0xFF000000,115200n8" \
91      -net nic,model=cadence_gem,netdev=net0 -netdev user,id=net0 \
92      -device virtio-rng-device,bus=virtio-mmio-bus.0,rng=rng0 \
93      -object rng-random,filename=/dev/urandom,id=rng0
94
95Boot PetaLinux 2019.2 via ARM Trusted Firmware (2018.3 because the 2019.2
96version of ATF tries to configure the CCI which we don't model) and U-boot:
97
98.. code-block:: bash
99
100  $ qemu-system-aarch64 -M xlnx-versal-virt -m 2G \
101      -serial stdio -display none \
102      -device loader,file=petalinux-v2018.3/bl31.elf,cpu-num=0 \
103      -device loader,file=petalinux-v2019.2/u-boot.elf \
104      -device loader,addr=0x20000000,file=petalinux-v2019.2/Image \
105      -nic user -nic user \
106      -device virtio-rng-device,bus=virtio-mmio-bus.0,rng=rng0 \
107      -object rng-random,filename=/dev/urandom,id=rng0
108
109Run the following at the U-Boot prompt:
110
111.. code-block:: bash
112
113  Versal>
114  fdt addr $fdtcontroladdr
115  fdt move $fdtcontroladdr 0x40000000
116  fdt set /timer clock-frequency <0x3dfd240>
117  setenv bootargs "rdinit=/sbin/init maxcpus=1 console=ttyAMA0,115200n8 earlycon=pl011,mmio,0xFF000000,115200n8"
118  booti 20000000 - 40000000
119  fdt addr $fdtcontroladdr
120
121Boot Linux as DOM0 on Xen via U-Boot:
122
123.. code-block:: bash
124
125  $ qemu-system-aarch64 -M xlnx-versal-virt -m 4G \
126      -serial stdio -display none \
127      -device loader,file=petalinux-v2019.2/u-boot.elf,cpu-num=0 \
128      -device loader,addr=0x30000000,file=linux/2018-04-24/xen \
129      -device loader,addr=0x40000000,file=petalinux-v2019.2/Image \
130      -nic user -nic user \
131      -device virtio-rng-device,bus=virtio-mmio-bus.0,rng=rng0 \
132      -object rng-random,filename=/dev/urandom,id=rng0
133
134Run the following at the U-Boot prompt:
135
136.. code-block:: bash
137
138  Versal>
139  fdt addr $fdtcontroladdr
140  fdt move $fdtcontroladdr 0x20000000
141  fdt set /timer clock-frequency <0x3dfd240>
142  fdt set /chosen xen,xen-bootargs "console=dtuart dtuart=/uart@ff000000 dom0_mem=640M bootscrub=0 maxcpus=1 timer_slop=0"
143  fdt set /chosen xen,dom0-bootargs "rdinit=/sbin/init clk_ignore_unused console=hvc0 maxcpus=1"
144  fdt mknode /chosen dom0
145  fdt set /chosen/dom0 compatible "xen,multiboot-module"
146  fdt set /chosen/dom0 reg <0x00000000 0x40000000 0x0 0x03100000>
147  booti 30000000 - 20000000
148
149Boot Linux as Dom0 on Xen via ARM Trusted Firmware and U-Boot:
150
151.. code-block:: bash
152
153  $ qemu-system-aarch64 -M xlnx-versal-virt -m 4G \
154      -serial stdio -display none \
155      -device loader,file=petalinux-v2018.3/bl31.elf,cpu-num=0 \
156      -device loader,file=petalinux-v2019.2/u-boot.elf \
157      -device loader,addr=0x30000000,file=linux/2018-04-24/xen \
158      -device loader,addr=0x40000000,file=petalinux-v2019.2/Image \
159      -nic user -nic user \
160      -device virtio-rng-device,bus=virtio-mmio-bus.0,rng=rng0 \
161      -object rng-random,filename=/dev/urandom,id=rng0
162
163Run the following at the U-Boot prompt:
164
165.. code-block:: bash
166
167  Versal>
168  fdt addr $fdtcontroladdr
169  fdt move $fdtcontroladdr 0x20000000
170  fdt set /timer clock-frequency <0x3dfd240>
171  fdt set /chosen xen,xen-bootargs "console=dtuart dtuart=/uart@ff000000 dom0_mem=640M bootscrub=0 maxcpus=1 timer_slop=0"
172  fdt set /chosen xen,dom0-bootargs "rdinit=/sbin/init clk_ignore_unused console=hvc0 maxcpus=1"
173  fdt mknode /chosen dom0
174  fdt set /chosen/dom0 compatible "xen,multiboot-module"
175  fdt set /chosen/dom0 reg <0x00000000 0x40000000 0x0 0x03100000>
176  booti 30000000 - 20000000
177
178