Re: [PATCH v2 4/9] pnv/xive2: Add NVG and NVC to cache watch facility

[Mike Kowal]

On 7/16/2024 2:29 AM, Cédric Le Goater wrote:
> On 7/15/24 20:33, Michael Kowal wrote:
> > From: Frederic Barrat <fbarrat@linux.ibm.com>
> >
> > The cache watch facility uses the same register interface to handle
> > entries in the NVP, NVG and NVC tables. A bit-field in the 'watchX
> > specification' register tells the table type. So far, that bit-field
> > was not read and the code assumed a read/write to the NVP table.
> >
> > This patch allows to read/write entries in the NVG and NVC table as
> > well.
> >
> > Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
> > Signed-off-by: Michael Kowal <kowal@linux.vnet.ibm.com>
> > ---
> >   hw/intc/pnv_xive2.c | 59 ++++++++++++++++++++++++++++++++-------------
> >   1 file changed, 42 insertions(+), 17 deletions(-)
> >
> > diff --git a/hw/intc/pnv_xive2.c b/hw/intc/pnv_xive2.c
> > index d62ac20d98..c72c66dd6a 100644
> > --- a/hw/intc/pnv_xive2.c
> > +++ b/hw/intc/pnv_xive2.c
> > @@ -462,46 +462,71 @@ static int pnv_xive2_write_nvp(Xive2Router 
> > *xrtr, uint8_t blk, uint32_t idx,
> >                                 word_number);
> >   }
> >   -static int pnv_xive2_nvp_update(PnvXive2 *xive, uint8_t watch_engine)
> > +static int pnv_xive2_nxc_to_table_type(uint8_t nxc_type, uint32_t 
> > *table_type)
> >   {
> > -    uint8_t  blk;
> > -    uint32_t idx;
> > +    switch (nxc_type) {
> > +    case PC_NXC_WATCH_NXC_NVP:
> > +        *table_type = VST_NVP;
> > +        break;
> > +    case PC_NXC_WATCH_NXC_NVG:
> > +        *table_type = VST_NVG;
> > +        break;
> > +    case PC_NXC_WATCH_NXC_NVC:
> > +        *table_type = VST_NVC;
> > +        break;
> > +    default:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                      "XIVE: invalid table type for nxc operation\n");
> > +        return -1;
> > +    }
> > +    return 0;
> > +}
> > +
> > +static int pnv_xive2_nxc_update(PnvXive2 *xive, uint8_t watch_engine)
> > +{
> > +    uint8_t  blk, nxc_type;
> > +    uint32_t idx, table_type = -1;
> >       int i, spec_reg, data_reg;
> >       uint64_t nxc_watch[4];
> >   -    if (watch_engine > 3) {
> > -        return -1;
> > -    }
> > +    assert(watch_engine < ARRAY_SIZE(nxc_watch));
> > +
>
> This belongs to patch 1.

I was trying to reduce the size of the first patch set and this could be 
isolated to separate patch set.  I can move it back to patch set 1.

Also note above, this is where I originally added the assert...

> >       spec_reg = (PC_NXC_WATCH0_SPEC + watch_engine * 0x40) >> 3;
> >       data_reg = (PC_NXC_WATCH0_DATA0 + watch_engine * 0x40) >> 3;
> > +    nxc_type = GETFIELD(PC_NXC_WATCH_NXC_TYPE, 
> > xive->pc_regs[spec_reg]);
> >       blk = GETFIELD(PC_NXC_WATCH_BLOCK_ID, xive->pc_regs[spec_reg]);
> >       idx = GETFIELD(PC_NXC_WATCH_INDEX, xive->pc_regs[spec_reg]);
> >   +    assert(pnv_xive2_nxc_to_table_type(nxc_type, &table_type));
> > +
> >       for (i = 0; i < ARRAY_SIZE(nxc_watch); i++) {
> >           nxc_watch[i] = cpu_to_be64(xive->pc_regs[data_reg + i]);
> >       }
> >   -    return pnv_xive2_vst_write(xive, VST_NVP, blk, idx, nxc_watch,
> > +    return pnv_xive2_vst_write(xive, table_type, blk, idx, nxc_watch,
> >                                 XIVE_VST_WORD_ALL);
> >   }
> >   -static void pnv_xive2_nvp_cache_load(PnvXive2 *xive, uint8_t 
> > watch_engine)
> > +static void pnv_xive2_nxc_cache_load(PnvXive2 *xive, uint8_t 
> > watch_engine)
> >   {
> > -    uint8_t  blk;
> > -    uint32_t idx;
> > +    uint8_t  blk, nxc_type;
> > +    uint32_t idx, table_type = -1;
> >       uint64_t nxc_watch[4] = { 0 };
> >       int i, spec_reg, data_reg;
> >   -    if (watch_engine > 3) {
> > -        return;
> > -    }
> > +    assert(watch_engine < ARRAY_SIZE(nxc_watch));
> > +
> >       spec_reg = (PC_NXC_WATCH0_SPEC + watch_engine * 0x40) >> 3;
> >       data_reg = (PC_NXC_WATCH0_DATA0 + watch_engine * 0x40) >> 3;
> > +    nxc_type = GETFIELD(PC_NXC_WATCH_NXC_TYPE, 
> > xive->pc_regs[spec_reg]);
> >       blk = GETFIELD(PC_NXC_WATCH_BLOCK_ID, xive->pc_regs[spec_reg]);
> >       idx = GETFIELD(PC_NXC_WATCH_INDEX, xive->pc_regs[spec_reg]);
> >   -    if (pnv_xive2_vst_read(xive, VST_NVP, blk, idx, nxc_watch)) {
> > -        xive2_error(xive, "VST: no NVP entry %x/%x !?", blk, idx);
> > +    assert(pnv_xive2_nxc_to_table_type(nxc_type, &table_type));
> > +
> > +    if (pnv_xive2_vst_read(xive, table_type, blk, idx, nxc_watch)) {
> > +        xive2_error(xive, "VST: no NXC entry %x/%x in %s table!?",
> > +                    blk, idx, vst_infos[table_type].name);
> >       }
> >         for (i = 0; i < ARRAY_SIZE(nxc_watch); i++) {
> > @@ -1431,7 +1456,7 @@ static uint64_t pnv_xive2_ic_pc_read(void 
> > *opaque, hwaddr offset,
> >           * SPEC register
> >           */
> >           watch_engine = (offset - PC_NXC_WATCH0_DATA0) >> 6;
> > -        pnv_xive2_nvp_cache_load(xive, watch_engine);
> > +        pnv_xive2_nxc_cache_load(xive, watch_engine);
> >           val = xive->pc_regs[reg];
> >           break;
> >   @@ -1505,7 +1530,7 @@ static void pnv_xive2_ic_pc_write(void 
> > *opaque, hwaddr offset,
> >           /* writing to DATA0 triggers the cache write */
> >           watch_engine = (offset - PC_NXC_WATCH0_DATA0) >> 6;
> >           xive->pc_regs[reg] = val;
> > -        pnv_xive2_nvp_update(xive, watch_engine);
> > +        pnv_xive2_nxc_update(xive, watch_engine);
> >           break;
> >        /* case PC_NXC_FLUSH_CTRL: */