ppce500.rst (6000B)
1 ppce500 generic platform (``ppce500``) 2 ====================================== 3 4 QEMU for PPC supports a special ``ppce500`` machine designed for emulation and 5 virtualization purposes. 6 7 Supported devices 8 ----------------- 9 10 The ``ppce500`` machine supports the following devices: 11 12 * PowerPC e500 series core (e500v2/e500mc/e5500/e6500) 13 * Configuration, Control, and Status Register (CCSR) 14 * Multicore Programmable Interrupt Controller (MPIC) with MSI support 15 * 1 16550A UART device 16 * 1 Freescale MPC8xxx I2C controller 17 * 1 Pericom pt7c4338 RTC via I2C 18 * 1 Freescale MPC8xxx GPIO controller 19 * Power-off functionality via one GPIO pin 20 * 1 Freescale MPC8xxx PCI host controller 21 * VirtIO devices via PCI bus 22 * 1 Freescale Enhanced Triple Speed Ethernet controller (eTSEC) 23 24 Hardware configuration information 25 ---------------------------------- 26 27 The ``ppce500`` machine automatically generates a device tree blob ("dtb") 28 which it passes to the guest, if there is no ``-dtb`` option. This provides 29 information about the addresses, interrupt lines and other configuration of 30 the various devices in the system. 31 32 If users want to provide their own DTB, they can use the ``-dtb`` option. 33 These DTBs should have the following requirements: 34 35 * The number of subnodes under /cpus node should match QEMU's ``-smp`` option 36 * The /memory reg size should match QEMU’s selected ram_size via ``-m`` 37 38 Both ``qemu-system-ppc`` and ``qemu-system-ppc64`` provide emulation for the 39 following 32-bit PowerPC CPUs: 40 41 * e500v2 42 * e500mc 43 44 Additionally ``qemu-system-ppc64`` provides support for the following 64-bit 45 PowerPC CPUs: 46 47 * e5500 48 * e6500 49 50 The CPU type can be specified via the ``-cpu`` command line. If not specified, 51 it creates a machine with e500v2 core. The following example shows an e6500 52 based machine creation: 53 54 .. code-block:: bash 55 56 $ qemu-system-ppc64 -nographic -M ppce500 -cpu e6500 57 58 Boot options 59 ------------ 60 61 The ``ppce500`` machine can start using the standard -kernel functionality 62 for loading a payload like an OS kernel (e.g.: Linux), or U-Boot firmware. 63 64 When -bios is omitted, the default pc-bios/u-boot.e500 firmware image is used 65 as the BIOS. QEMU follows below truth table to select which payload to execute: 66 67 ===== ========== ======= 68 -bios -kernel payload 69 ===== ========== ======= 70 N N u-boot 71 N Y kernel 72 Y don't care u-boot 73 ===== ========== ======= 74 75 When both -bios and -kernel are present, QEMU loads U-Boot and U-Boot in turns 76 automatically loads the kernel image specified by the -kernel parameter via 77 U-Boot's built-in "bootm" command, hence a legacy uImage format is required in 78 such scenario. 79 80 Running Linux kernel 81 -------------------- 82 83 Linux mainline v5.11 release is tested at the time of writing. To build a 84 Linux mainline kernel that can be booted by the ``ppce500`` machine in 85 64-bit mode, simply configure the kernel using the defconfig configuration: 86 87 .. code-block:: bash 88 89 $ export ARCH=powerpc 90 $ export CROSS_COMPILE=powerpc-linux- 91 $ make corenet64_smp_defconfig 92 $ make menuconfig 93 94 then manually select the following configuration: 95 96 Platform support > Freescale Book-E Machine Type > QEMU generic e500 platform 97 98 To boot the newly built Linux kernel in QEMU with the ``ppce500`` machine: 99 100 .. code-block:: bash 101 102 $ qemu-system-ppc64 -M ppce500 -cpu e5500 -smp 4 -m 2G \ 103 -display none -serial stdio \ 104 -kernel vmlinux \ 105 -initrd /path/to/rootfs.cpio \ 106 -append "root=/dev/ram" 107 108 To build a Linux mainline kernel that can be booted by the ``ppce500`` machine 109 in 32-bit mode, use the same 64-bit configuration steps except the defconfig 110 file should use corenet32_smp_defconfig. 111 112 To boot the 32-bit Linux kernel: 113 114 .. code-block:: bash 115 116 $ qemu-system-ppc64 -M ppce500 -cpu e500mc -smp 4 -m 2G \ 117 -display none -serial stdio \ 118 -kernel vmlinux \ 119 -initrd /path/to/rootfs.cpio \ 120 -append "root=/dev/ram" 121 122 Running U-Boot 123 -------------- 124 125 U-Boot mainline v2021.07 release is tested at the time of writing. To build a 126 U-Boot mainline bootloader that can be booted by the ``ppce500`` machine, use 127 the qemu-ppce500_defconfig with similar commands as described above for Linux: 128 129 .. code-block:: bash 130 131 $ export CROSS_COMPILE=powerpc-linux- 132 $ make qemu-ppce500_defconfig 133 134 You will get u-boot file in the build tree. 135 136 When U-Boot boots, you will notice the following if using with ``-cpu e6500``: 137 138 .. code-block:: none 139 140 CPU: Unknown, Version: 0.0, (0x00000000) 141 Core: e6500, Version: 2.0, (0x80400020) 142 143 This is because we only specified a core name to QEMU and it does not have a 144 meaningful SVR value which represents an actual SoC that integrates such core. 145 You can specify a real world SoC device that QEMU has built-in support but all 146 these SoCs are e500v2 based MPC85xx series, hence you cannot test anything 147 built for P4080 (e500mc), P5020 (e5500) and T2080 (e6500). 148 149 Networking 150 ---------- 151 152 By default a VirtIO standard PCI networking device is connected as an ethernet 153 interface at PCI address 0.1.0, but we can switch that to an e1000 NIC by: 154 155 .. code-block:: bash 156 157 $ qemu-system-ppc64 -M ppce500 -smp 4 -m 2G \ 158 -display none -serial stdio \ 159 -bios u-boot \ 160 -nic tap,ifname=tap0,script=no,downscript=no,model=e1000 161 162 The QEMU ``ppce500`` machine can also dynamically instantiate an eTSEC device 163 if “-device eTSEC” is given to QEMU: 164 165 .. code-block:: bash 166 167 -netdev tap,ifname=tap0,script=no,downscript=no,id=net0 -device eTSEC,netdev=net0 168 169 Root file system on flash drive 170 ------------------------------- 171 172 Rather than using a root file system on ram disk, it is possible to have it on 173 CFI flash. Given an ext2 image whose size must be a power of two, it can be used 174 as follows: 175 176 .. code-block:: bash 177 178 $ qemu-system-ppc64 -M ppce500 -cpu e500mc -smp 4 -m 2G \ 179 -display none -serial stdio \ 180 -kernel vmlinux \ 181 -drive if=pflash,file=/path/to/rootfs.ext2,format=raw \ 182 -append "rootwait root=/dev/mtdblock0"