Re: [Qemu-devel] [PATCH 2/7] PPC: Make MPC8544DS emulation work w/o KVM

[Blue Swirl <blauwirbel@gmail.com>]

On Sun, May 8, 2011 at 2:00 AM, Alexander Graf <agraf@suse.de> wrote:
> The MPC8544DS board emulation was only used with KVM so far, so some
> parts of the code didn't provide proper values for non-KVM execution.
>
> This patch makes the machine work without KVM enabled. To actually use
> this, you also need proper e500v2 MMU emulation.
>
> Signed-off-by: Alexander Graf <agraf@suse.de>
>
> ---
>
> v2 -> v3:
>
>  - fix mpc initial tlb size comment
>  - enable cpu reset
> ---
>  hw/ppce500_mpc8544ds.c |   86 +++++++++++++++++++++++++++++++++++++++--------
>  1 files changed, 71 insertions(+), 15 deletions(-)
>
> diff --git a/hw/ppce500_mpc8544ds.c b/hw/ppce500_mpc8544ds.c
> index 1b8a1c4..44d6440 100644
> --- a/hw/ppce500_mpc8544ds.c
> +++ b/hw/ppce500_mpc8544ds.c
> @@ -28,6 +28,7 @@
>  #include "kvm_ppc.h"
>  #include "device_tree.h"
>  #include "openpic.h"
> +#include "ppc.h"
>  #include "ppce500.h"
>  #include "loader.h"
>  #include "elf.h"
> @@ -50,6 +51,12 @@
>  #define MPC8544_PCI_IO             0xE1000000
>  #define MPC8544_PCI_IOLEN          0x10000
>
> +static struct boot_info
> +{
> +    uint32_t dt_base;
> +    uint32_t entry;
> +} boot_info;

I don't think there is a need to use static state here.

> +
>  #ifdef CONFIG_FDT
>  static int mpc8544_copy_soc_cell(void *fdt, const char *node, const char *prop)
>  {
> @@ -82,7 +89,7 @@ static int mpc8544_load_device_tree(target_phys_addr_t addr,
>  {
>     int ret = -1;
>  #ifdef CONFIG_FDT
> -    uint32_t mem_reg_property[] = {0, ramsize};
> +    uint32_t mem_reg_property[] = {0, cpu_to_be32(ramsize)};
>     char *filename;
>     int fdt_size;
>     void *fdt;
> @@ -103,15 +110,19 @@ static int mpc8544_load_device_tree(target_phys_addr_t addr,
>     if (ret < 0)
>         fprintf(stderr, "couldn't set /memory/reg\n");
>
> -    ret = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
> -                                    initrd_base);
> -    if (ret < 0)
> -        fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
> +    if (initrd_size) {
> +        ret = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
> +                                        initrd_base);
> +        if (ret < 0) {
> +            fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
> +        }
>
> -    ret = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
> -                                    (initrd_base + initrd_size));
> -    if (ret < 0)
> -        fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
> +        ret = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
> +                                        (initrd_base + initrd_size));
> +        if (ret < 0) {
> +            fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
> +        }
> +    }
>
>     ret = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
>                                       kernel_cmdline);
> @@ -145,6 +156,13 @@ static int mpc8544_load_device_tree(target_phys_addr_t addr,
>
>         mpc8544_copy_soc_cell(fdt, buf, "clock-frequency");
>         mpc8544_copy_soc_cell(fdt, buf, "timebase-frequency");
> +    } else {
> +        const uint32_t freq = 400000000;
> +
> +        qemu_devtree_setprop_cell(fdt, "/cpus/PowerPC,8544@0",
> +                                  "clock-frequency", freq);
> +        qemu_devtree_setprop_cell(fdt, "/cpus/PowerPC,8544@0",
> +                                  "timebase-frequency", freq);
>     }
>
>     ret = rom_add_blob_fixed(BINARY_DEVICE_TREE_FILE, fdt, fdt_size, addr);
> @@ -156,6 +174,35 @@ out:
>     return ret;
>  }
>
> +/* Create -kernel TLB entries for BookE, linearly spanning 256MB.  */
> +static void mmubooke_create_initial_mapping(CPUState *env,
> +                                     target_ulong va,
> +                                     target_phys_addr_t pa)
> +{
> +    ppcemb_tlb_t *tlb = &env->tlb[512].tlbe;
> +
> +    tlb->attr = 0;
> +    tlb->prot = PAGE_VALID | ((PAGE_READ | PAGE_WRITE | PAGE_EXEC) << 4);
> +    tlb->size = 256 * 1024 * 1024;
> +    tlb->EPN = va & TARGET_PAGE_MASK;
> +    tlb->RPN = pa & TARGET_PAGE_MASK;
> +    tlb->PID = 0;
> +}
> +
> +static void mpc8544ds_cpu_reset(void *opaque)
> +{
> +    CPUState *env = opaque;
> +    struct boot_info *bi = env->load_info;
> +
> +    cpu_reset(env);
> +
> +    /* Set initial guest state. */
> +    env->gpr[1] = (16<<20) - 8;
> +    env->gpr[3] = bi->dt_base;
> +    env->nip = bi->entry;
> +    mmubooke_create_initial_mapping(env, 0, 0);
> +}
> +
>  static void mpc8544ds_init(ram_addr_t ram_size,
>                          const char *boot_device,
>                          const char *kernel_filename,
> @@ -188,6 +235,13 @@ static void mpc8544ds_init(ram_addr_t ram_size,
>         exit(1);
>     }
>
> +    /* XXX register timer? */
> +    ppc_emb_timers_init(env, 400000000, PPC_INTERRUPT_DECR);
> +    ppc_dcr_init(env, NULL, NULL);
> +
> +    /* Register reset handler */
> +    qemu_register_reset(mpc8544ds_cpu_reset, env);
> +
>     /* Fixup Memory size on a alignment boundary */
>     ram_size &= ~(RAM_SIZES_ALIGN - 1);
>
> @@ -265,6 +319,9 @@ static void mpc8544ds_init(ram_addr_t ram_size,
>
>     /* If we're loading a kernel directly, we must load the device tree too. */
>     if (kernel_filename) {
> +#ifndef CONFIG_FDT
> +        cpu_abort(env, "Compiled without FDT support - can't load kernel\n");
> +#endif
>         dt_base = (kernel_size + DTC_LOAD_PAD) & ~DTC_PAD_MASK;
>         if (mpc8544_load_device_tree(dt_base, ram_size,
>                     initrd_base, initrd_size, kernel_cmdline) < 0) {
> @@ -272,15 +329,14 @@ static void mpc8544ds_init(ram_addr_t ram_size,
>             exit(1);
>         }
>
> -        /* Set initial guest state. */
> -        env->gpr[1] = (16<<20) - 8;
> -        env->gpr[3] = dt_base;
> -        env->nip = entry;
> -        /* XXX we currently depend on KVM to create some initial TLB entries. */
> +        boot_info.entry = entry;
> +        boot_info.dt_base = dt_base;
>     }
> +    env->load_info = &boot_info;
>
> -    if (kvm_enabled())
> +    if (kvm_enabled()) {
>         kvmppc_init();
> +    }
>
>     return;
>  }
> --
> 1.6.0.2
>
>
>