Re: [Qemu-devel] sh4: r2d --append option support

[Aurelien Jarno <aurelien@aurel32.net>]

On Sat, Mar 28, 2009 at 11:51:00PM +0100, Aurelien Jarno wrote:
> On Sun, Mar 08, 2009 at 03:00:17AM +0900, takasi-y@ops.dti.ne.jp wrote:
> > Add linux kernel command line ("--append" option) support.
> > Fix kernel loading address to appropriate position when --append used.
> > Using --kernel but --append case is left untouched for backward compatibility.
> > 
> > This also change the host<->SH address mapping for r2d to
> >  host addr == phys_ram_base + SH addr.
> > 
> > Signed-off-by: Takashi YOSHII <takasi-y@ops.dti.ne.jp>
> > ---
> > Hi,
> > 
> > > You should use pstrcpy_targphys() instead and remove phys_ram_base.
> > > Otherwise looks good.
> > This reminds me of host/target address mapping of r2d, which is currently
> >  host addr == phys_ram_base + SH addr - 0x0c000000 (== top of SDRAM)
> > This patch change it to
> >  host addr == phys_ram_base + SH addr
> > 
> > That one itself is not a problem because QEMU's core memory system allows the
> >  constant offset between host and target, but functions in loader.c.
> > 
> > Of course I could write as pstrcpy_targphys(0x10100, 256, kernel_cmdline);
> > But, I think this is confusing because arg for *_targphys() that typed
> >  target_phy_addr_t is not equal to target's physical address.
> > 
> > And other one....
> > Last time, loading offset was 0x80000, but was my mistake. Fixed to 0x800000.
> > 
> > /yoshii
> > 
> > ---
> >  hw/r2d.c |   21 ++++++++++++++++-----
> >  1 files changed, 16 insertions(+), 5 deletions(-)
> > 
> > diff --git a/hw/r2d.c b/hw/r2d.c
> > index 713fc53..0f70d16 100644
> > --- a/hw/r2d.c
> > +++ b/hw/r2d.c
> > @@ -37,6 +37,9 @@
> >  
> >  #define SM501_VRAM_SIZE 0x800000
> >  
> > +/* CONFIG_BOOT_LINK_OFFSET of Linux kernel */
> > +#define LINUX_LOAD_OFFSET 0x800000
> > +
> >  #define PA_IRLMSK	0x00
> >  #define PA_POWOFF	0x30
> >  #define PA_VERREG	0x32
> > @@ -212,6 +215,7 @@ static void r2d_init(ram_addr_t ram_size, int vga_ram_size,
> >      }
> >  
> >      /* Allocate memory space */
> > +    qemu_ram_alloc(SDRAM_BASE); /* to adjust the offset */
> 
> This should not be needed, as long as you access to the target address
> space using dedicated functions. For which reason do you added it?
> 
> >      sdram_addr = qemu_ram_alloc(SDRAM_SIZE);
> >      cpu_register_physical_memory(SDRAM_BASE, SDRAM_SIZE, sdram_addr);
> >      /* Register peripherals */
> > @@ -233,20 +237,27 @@ static void r2d_init(ram_addr_t ram_size, int vga_ram_size,
> >          pci_nic_init(pci, &nd_table[i], (i==0)? 2<<3: -1, "rtl8139");
> >  
> >      /* Todo: register on board registers */
> > -    {
> > +    if (kernel_filename) {
> >        int kernel_size;
> >        /* initialization which should be done by firmware */
> >        stl_phys(SH7750_BCR1, 1<<3); /* cs3 SDRAM */
> >        stw_phys(SH7750_BCR2, 3<<(3*2)); /* cs3 32bit */
> >  
> > -      kernel_size = load_image(kernel_filename, phys_ram_base);
> > +      if (kernel_cmdline) {
> > +          kernel_size = load_image_targphys(kernel_filename,
> > +				   SDRAM_BASE + LINUX_LOAD_OFFSET,
> > +				   SDRAM_SIZE - LINUX_LOAD_OFFSET);
> > +          env->pc = (SDRAM_BASE + LINUX_LOAD_OFFSET) | 0xa0000000;
> > +          pstrcpy_targphys(SDRAM_BASE + 0x10100, 256, kernel_cmdline);
> > +      } else {
> > +          kernel_size = load_image(kernel_filename, SDRAM_BASE);
> 
> It think it should be:
> 
>              kernel_size = load_image_targphys(kernel_filename, SDRAM_BASE, SDRAM_SIZE);
> 
> > +          env->pc = SDRAM_BASE | 0xa0000000; /* Start from P2 area */
> > +      }
> >  
> >        if (kernel_size < 0) {
> >          fprintf(stderr, "qemu: could not load kernel '%s'\n", kernel_filename);
> >          exit(1);
> >        }
> > -
> > -      env->pc = SDRAM_BASE | 0xa0000000; /* Start from P2 area */
> >      }
> >  }
> >  
> > @@ -254,5 +265,5 @@ QEMUMachine r2d_machine = {
> >      .name = "r2d",
> >      .desc = "r2d-plus board",
> >      .init = r2d_init,
> > -    .ram_require = (SDRAM_SIZE + SM501_VRAM_SIZE) | RAMSIZE_FIXED,
> > +    .ram_require = (SDRAM_BASE + SDRAM_SIZE + SM501_VRAM_SIZE) | RAMSIZE_FIXED,
> 
> I think this is needed because of the "qemu_ram_alloc(SDRAM_BASE);"
> line. They should probably be removed alltogether.
> 
> >  };

I have actually committed your patch by mistake, so I have made the
suggested changes to the SVN. I am still able to boot and SH4 kernel on
the R2D board with them.

-- 
Aurelien Jarno	                        GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net