Re: [Qemu-devel] [PATCHv3 02/14] unicore32-softmmu: Add coprocessor 0(sysctrl) and 1(ocd) instruction support

[Guan Xuetao <gxt@mprc.pku.edu.cn>]

On Mon, 2012-06-18 at 19:51 +0000, Blue Swirl wrote:
> On Mon, Jun 18, 2012 at 9:24 AM, Guan Xuetao <gxt@mprc.pku.edu.cn> wrote:
> > Coprocessor 0 is system control coprocessor, and we need get/set its contents.
> > Also, all cache/tlb ops shoule be implemented here, but just ignored with no harm.
> >
> > Coprocessor 1 is OCD (on-chip-debugger), which is used for faked console,
> > so we could output chars to this console without graphic card.
> >
> > Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
> > ---
> >  target-unicore32/helper.c    |  177 +++++++++++++++++++++++++++++++++---------
> >  target-unicore32/helper.h    |   17 ++---
> >  target-unicore32/translate.c |   75 ++++++++++++++++++-
> >  3 files changed, 221 insertions(+), 48 deletions(-)
> >
> > diff --git a/target-unicore32/helper.c b/target-unicore32/helper.c
> > index 9b8ff06..42a39e5 100644
> > --- a/target-unicore32/helper.c
> > +++ b/target-unicore32/helper.c
> > @@ -14,6 +14,14 @@
> >  #include "helper.h"
> >  #include "host-utils.h"
> >
> > +#undef DEBUG_UC32
> > +
> > +#ifdef DEBUG_UC32
> > +#define DPRINTF(fmt, ...) printf("%s: " fmt , __func__, ## __VA_ARGS__)
> > +#else
> > +#define DPRINTF(fmt, ...) do {} while (0)
> > +#endif
> > +
> >  CPUUniCore32State *uc32_cpu_init(const char *cpu_model)
> >  {
> >     UniCore32CPU *cpu;
> > @@ -45,6 +53,138 @@ uint32_t HELPER(clz)(uint32_t x)
> >     return clz32(x);
> >  }
> >
> > +#ifndef CONFIG_USER_ONLY
> > +void helper_cp0_set(CPUUniCore32State *env, uint32_t val, uint32_t creg,
> > +        uint32_t cop)
> > +{
> > +    /*
> > +     * movc pp.nn, rn, #imm9
> > +     *      rn: UCOP_REG_D
> > +     *      nn: UCOP_REG_N
> > +     *          1: sys control reg.
> > +     *          2: page table base reg.
> > +     *          3: data fault status reg.
> > +     *          4: insn fault status reg.
> > +     *          5: cache op. reg.
> > +     *          6: tlb op. reg.
> > +     *      imm9: split UCOP_IMM10 with bit5 is 0
> > +     */
> > +    switch (creg) {
> > +    case 1:
> > +        if (cop != 0) goto unrecognized;
> 
> Does this pass scripts/checkpatch.pl? These should become
> if (cop != 0) {
>     goto unrecognized;
> }
Thanks for pointing it out, and sorry for that.
I will correct it in next version.

> 
> > +        env->cp0.c1_sys = val;
> > +        break;
> > +    case 2:
> > +        if (cop != 0) goto unrecognized;
> > +        env->cp0.c2_base = val;
> > +        break;
> > +    case 3:
> > +        if (cop != 0) goto unrecognized;
> > +        env->cp0.c3_faultstatus = val;
> > +        break;
> > +    case 4:
> > +        if (cop != 0) goto unrecognized;
> > +        env->cp0.c4_faultaddr = val;
> > +        break;
> > +    case 5:
> > +        switch(cop) {
> > +        case 28:
> > +            DPRINTF("Invalidate Entire I&D cache\n");
> > +            return;
> > +        case 20:
> > +            DPRINTF("Invalidate Entire Icache\n");
> > +            return;
> > +        case 12:
> > +            DPRINTF("Invalidate Entire Dcache\n");
> > +            return;
> > +        case 10:
> > +            DPRINTF("Clean Entire Dcache\n");
> > +            return;
> > +        case 14:
> > +            DPRINTF("Flush Entire Dcache\n");
> > +            return;
> > +        case 13:
> > +            DPRINTF("Invalidate Dcache line\n");
> > +            return;
> > +        case 11:
> > +            DPRINTF("Clean Dcache line\n");
> > +            return;
> > +        case 15:
> > +            DPRINTF("Flush Dcache line\n");
> > +            return;
> > +        }
> > +        break;
> > +    case 6:
> > +        if ((cop <= 6) && (cop >=2)) {
> > +            /* invalid all tlb */
> > +            tlb_flush(env, 1);
> > +            return;
> > +        }
> > +        break;
> > +    default:
> > +        goto unrecognized;
> > +    }
> > +    return;
> > +unrecognized:
> > +    cpu_abort(env, "Wrong register (%d) or wrong operation (%d) in cp0_set!\n",
> > +            creg, cop);
> 
> The call to cpu_abort() would mean that the guest is able to terminate
> QEMU at will, which is not OK. What does real HW do?
In my opinion, I just want to terminate qemu when any unhandled or
unknown operations happen.

> 
> > +}
> > +
> > +uint32_t helper_cp0_get(CPUUniCore32State *env, uint32_t creg, uint32_t cop)
> > +{
> > +    /*
> > +     * movc rd, pp.nn, #imm9
> > +     *      rd: UCOP_REG_D
> > +     *      nn: UCOP_REG_N
> > +     *          0: cpuid and cachetype
> > +     *          1: sys control reg.
> > +     *          2: page table base reg.
> > +     *          3: data fault status reg.
> > +     *          4: insn fault status reg.
> > +     *      imm9: split UCOP_IMM10 with bit5 is 0
> > +     */
> > +    switch (creg) {
> > +    case 0:
> > +        switch (cop) {
> > +        case 0:
> > +            return env->cp0.c0_cpuid;
> > +        case 1:
> > +            return env->cp0.c0_cachetype;
> > +        }
> > +        break;
> > +    case 1:
> > +        if (cop == 0) {
> > +            return env->cp0.c1_sys;
> > +        }
> > +        break;
> > +    case 2:
> > +        if (cop == 0) {
> > +            return env->cp0.c2_base;
> > +        }
> > +        break;
> > +    case 3:
> > +        if (cop == 0) {
> > +            return env->cp0.c3_faultstatus;
> > +        }
> > +        break;
> > +    case 4:
> > +        if (cop == 0) {
> > +            return env->cp0.c4_faultaddr;
> > +        }
> > +        break;
> > +    }
> > +    cpu_abort(env, "Wrong register (%d) or wrong operation (%d) in cp0_set!\n",
> > +            creg, cop);
> > +}
> > +
> > +void helper_cp1_putc(target_ulong x)
> > +{
> > +    printf("%c", x);
> > +    fflush(NULL);
> > +    return;
> 
> Useless return.
Yes, thanks.

> 
> The printout should be enabled only for DEBUG_UC32.
Here, I just want to print a char in the text console.
I tried printw and addch under curses environment, but their color
schemes had some problems in my server, and I must call scrollok() at
every new-line. (scrl() didn't work) So, I left printf here to output a
character from ocd_console in kernel, and it works.

Thanks & Regards,

Guan Xuetao