Re: [Qemu-devel] [PATCH] prep: Fix software reset

["Andreas Färber" <andreas.faerber@web.de>]

Am 16.02.2013 16:08, schrieb Julio Guerra:
> The software reset of a PReP machine should reset the entire system
> and not only the processor. It occurs when changing the 7th bit of
> port 0092 from 0 to 1.
> 
> Adding a new variable in PReP's sysctrl_t to store the soft reset bit
> makes possible to be compliant with PReP specification :
> * reset the system when changing soft reset bit from 0 to 1.
> * the soft reset bit value is 1 after a soft reset.
> * Port 0092 is read/write.
> 
> qemu_system_reset_request() does the required job (calling the reset
> handlers) when the software reset is needed.
> 
> reset_irq is no longer needed, the CPU reset (calling ppc_prep_reset)
> is called when qemu_system_reset calls every reset handlers.
> 
> Signed-off-by: Julio Guerra <guerr@julio.in>
> ---
>  hw/ppc/prep.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/ppc/prep.c b/hw/ppc/prep.c
> index e06dded..64dab8b 100644
> --- a/hw/ppc/prep.c
> +++ b/hw/ppc/prep.c
> @@ -178,12 +178,12 @@ static const MemoryRegionOps PPC_XCSR_ops = {
> 
>  /* Fake super-io ports for PREP platform (Intel 82378ZB) */
>  typedef struct sysctrl_t {
> -    qemu_irq reset_irq;
>      M48t59State *nvram;
>      uint8_t state;
>      uint8_t syscontrol;
>      int contiguous_map;
>      int endian;
> +    uint8_t sreset;
>  } sysctrl_t;
> 
>  enum {
> @@ -203,9 +203,11 @@ static void PREP_io_800_writeb (void *opaque, uint32_t addr, uint32_t val)
>          /* Special port 92 */
>          /* Check soft reset asked */
>          if (val & 0x01) {
> -            qemu_irq_raise(sysctrl->reset_irq);
> +	    if (!sysctrl->sreset)
> +                qemu_system_reset_request();
> +            sysctrl->sreset = 1;
>          } else {
> -            qemu_irq_lower(sysctrl->reset_irq);
> +            sysctrl->sreset = 0;
>          }
>          /* Check LE mode */
>          if (val & 0x02) {

> @@ -267,7 +269,7 @@ static uint32_t PREP_io_800_readb (void *opaque, uint32_t addr)
>      switch (addr) {
>      case 0x0092:
>          /* Special port 92 */
> -        retval = 0x00;
> +        retval = (sysctrl->endian << 1)

Thanks, applied this bit to prep-up:
http://repo.or.cz/w/qemu/afaerber.git/shortlog/refs/heads/prep-up

Andreas

> | sysctrl->sreset;
>          break;
>      case 0x0800:
>          /* Motorola CPU configuration register */
> @@ -624,7 +626,8 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
>      }
>      isa_create_simple(isa_bus, "i8042");
> 
> -    sysctrl->reset_irq = first_cpu->irq_inputs[PPC6xx_INPUT_HRESET];
> +    sysctrl->sreset = 0;
> +    sysctrl->endian = 0;
>      /* System control ports */
>      register_ioport_read(0x0092, 0x01, 1, &PREP_io_800_readb, sysctrl);
>      register_ioport_write(0x0092, 0x01, 1, &PREP_io_800_writeb, sysctrl);
> --
> 1.8.1.2
>