| Message ID | 1519940751-9022-1-git-send-email-arbab@linux.vnet.ibm.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | npu2: Use unfiltered mode in XTS tables | expand |
Thanks Reza! I had one very minor thought below but it doesn't require a respin - everything looks correct and seemed to work on our limited test setup. Note I was only able to excersise the translation request path and not the shootdown path as we lack an application stack to test ATSDs. Acked-by: Alistair Popple <alistair@popple.id.au> > -static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) > +static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid __unused, > + uint64_t bdf) > { > struct phb *phb = pci_get_phb(phb_id); > struct npu2 *p = phb_to_npu2(phb); > - uint64_t xts_bdf, xts_bdf_pid; > - uint64_t lparshort; > - int id, rc = 0; > + uint64_t xts_bdf; > + int rc = 0; > > if (!phb || phb->phb_type != phb_type_npu_v2) > return OPAL_PARAMETER; > @@ -2137,26 +2136,13 @@ static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) > &xts_bdf, NPU2_XTS_BDF_MAP_BDF) < 0) { > NPU2ERR(p, "LPARID not associated with any GPU\n"); I guess this check is still somewhat useful to catch a buggy device driver out but I'm not convinced it provides much value - we could just as easily remove it as well. > rc = OPAL_PARAMETER; > - goto out; > } > > - lparshort = GETFIELD(NPU2_XTS_BDF_MAP_LPARSHORT, xts_bdf); > - NPU2DBG(p, "Found LPARSHORT = 0x%llx destroy context for BDF = 0x%03llx PID = 0x%llx\n", > - lparshort, bdf, pid); > - > - /* Now find the entry in the bdf/pid table */ > - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_LPARSHORT, 0ul, lparshort); > - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_PASID, xts_bdf_pid, pid); > - id = npu_table_search(p, NPU2_XTS_PID_MAP, 0x20, NPU2_XTS_PID_MAP_SIZE, &xts_bdf_pid, > - NPU2_XTS_PID_MAP_LPARSHORT | NPU2_XTS_PID_MAP_PASID); > - if (id < 0) { > - rc = OPAL_PARAMETER; > - goto out; > - } > + /* > + * The bdf/pid table only contains wildcard entries, so we don't > + * need to remove anything here. > + */ > > - /* And zero the entry */ > - npu2_write(p, NPU2_XTS_PID_MAP + id*0x20, 0); > -out: > unlock(&p->lock); > return rc; > } > @@ -2208,6 +2194,7 @@ static int opal_npu_map_lpar(uint64_t phb_id, uint64_t bdf, uint64_t lparid, > } > > xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_VALID, 0UL, 1); > + xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_UNFILT, xts_bdf_lpar, 1); > xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_BDF, xts_bdf_lpar, bdf); > > /* We only support radix for the moment */ > diff --git a/include/npu2-regs.h b/include/npu2-regs.h > index 73925f9..fd249f4 100644 > --- a/include/npu2-regs.h > +++ b/include/npu2-regs.h > @@ -425,6 +425,7 @@ void npu2_write_mask(struct npu2 *p, uint64_t reg, uint64_t val, uint64_t mask); > #define NPU2_XTS_MMIO_ATSD7_LPARID NPU2_REG_OFFSET(NPU2_STACK_MISC, NPU2_BLOCK_XTS, 0x138) > #define NPU2_XTS_BDF_MAP NPU2_REG_OFFSET(NPU2_STACK_MISC, NPU2_BLOCK_XTS, 0x4000) > #define NPU2_XTS_BDF_MAP_VALID PPC_BIT(0) > +#define NPU2_XTS_BDF_MAP_UNFILT PPC_BIT(1) > #define NPU2_XTS_BDF_MAP_STACK PPC_BITMASK(4, 6) > #define NPU2_XTS_BDF_MAP_BRICK PPC_BIT(7) > #define NPU2_XTS_BDF_MAP_BDF PPC_BITMASK(16, 31) > @@ -437,6 +438,7 @@ void npu2_write_mask(struct npu2 *p, uint64_t reg, uint64_t val, uint64_t mask); > #define NPU2_XTS_PID_MAP_VALID_ATRGPA0 PPC_BIT(0) > #define NPU2_XTS_PID_MAP_VALID_ATRGPA1 PPC_BIT(1) > #define NPU2_XTS_PID_MAP_VALID_ATSD PPC_BIT(2) > +#define NPU2_XTS_PID_MAP_MSR PPC_BITMASK(25,31) > #define NPU2_XTS_PID_MAP_MSR_DR PPC_BIT(25) > #define NPU2_XTS_PID_MAP_MSR_TA PPC_BIT(26) > #define NPU2_XTS_PID_MAP_MSR_HV PPC_BIT(27) >
On Fri, Mar 09, 2018 at 10:33:51AM +1100, Alistair Popple wrote: >> -static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) >> +static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid __unused, >> + uint64_t bdf) >> { >> struct phb *phb = pci_get_phb(phb_id); >> struct npu2 *p = phb_to_npu2(phb); >> - uint64_t xts_bdf, xts_bdf_pid; >> - uint64_t lparshort; >> - int id, rc = 0; >> + uint64_t xts_bdf; >> + int rc = 0; >> >> if (!phb || phb->phb_type != phb_type_npu_v2) >> return OPAL_PARAMETER; >> @@ -2137,26 +2136,13 @@ static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) >> &xts_bdf, NPU2_XTS_BDF_MAP_BDF) < 0) { >> NPU2ERR(p, "LPARID not associated with any GPU\n"); > >I guess this check is still somewhat useful to catch a buggy device driver out >but I'm not convinced it provides much value - we could just as easily remove it >as well. Yeah, I wavered on it a bit and figured if nothing else, the function could still keep validating that argument. There are some words to that effect in the commit log.
> Yeah, I wavered on it a bit and figured if nothing else, the function > could still keep validating that argument. There are some words to that > effect in the commit log. Yeah, I saw that. Good work on the commit log btw - it's a good description of what we're doing here. - Alistair
Reza Arbab <arbab@linux.vnet.ibm.com> writes: > The XTS_PID context table is limited to 256 possible pids/contexts. To > relieve this limitation, make use of "unfiltered mode" instead. > > If an entry in the XTS_BDF table has the bit for unfiltered mode set, we > can just use one context for that entire bdf/lpar, regardless of pid. > Instead of of searching the XTS_PID table, the NMMU checkout request > will simply use the entry indexed by lparshort id instead. > > Change opal_npu_init_context() to create these lparshort-indexed > wildcard entries (0-15) instead of allocating one for each pid. Check > that multiple calls for the same bdf all specify the same msr value. > > In opal_npu_destroy_context(), continue validating the bdf argument, > ensuring that it actually maps to an lpar, but no longer remove anything > from the XTS_PID table. If/when we start supporting virtualized GPUs, we > might consider actually removing these wildcard entries by keeping a > refcount, but keep things simple for now. > > Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> > --- > hw/npu2.c | 73 ++++++++++++++++++++++------------------------------- > include/npu2-regs.h | 2 ++ > 2 files changed, 32 insertions(+), 43 deletions(-) Thanks, merged to master as of 105d80f85b071e1aefefaa4e15beaee027a45fd6
diff --git a/hw/npu2.c b/hw/npu2.c index fad53c4..2a56ac6 100644 --- a/hw/npu2.c +++ b/hw/npu2.c @@ -2039,13 +2039,13 @@ static int npu_table_search(struct npu2 *p, uint64_t table_addr, int stride, * allocated. */ #define NPU2_VALID_ATS_MSR_BITS (MSR_DR | MSR_HV | MSR_PR | MSR_SF) -static int64_t opal_npu_init_context(uint64_t phb_id, int pasid, uint64_t msr, - uint64_t bdf) +static int64_t opal_npu_init_context(uint64_t phb_id, int pasid __unused, + uint64_t msr, uint64_t bdf) { struct phb *phb = pci_get_phb(phb_id); struct npu2 *p = phb_to_npu2(phb); - uint64_t xts_bdf, xts_bdf_pid = 0; - int id, lparshort; + uint64_t xts_bdf, old_xts_bdf_pid, xts_bdf_pid; + int id; if (!phb || phb->phb_type != phb_type_npu_v2) return OPAL_PARAMETER; @@ -2069,20 +2069,8 @@ static int64_t opal_npu_init_context(uint64_t phb_id, int pasid, uint64_t msr, goto out; } - lparshort = GETFIELD(NPU2_XTS_BDF_MAP_LPARSHORT, xts_bdf); - NPU2DBG(p, "Found LPARSHORT = 0x%x for BDF = 0x%03llx\n", lparshort, - bdf); - - /* - * Need to find a free context. - */ - id = npu_table_search(p, NPU2_XTS_PID_MAP, 0x20, NPU2_XTS_PID_MAP_SIZE, - &xts_bdf_pid, -1UL); - if (id < 0) { - NPU2ERR(p, "No XTS contexts available\n"); - id = OPAL_RESOURCE; - goto out; - } + id = GETFIELD(NPU2_XTS_BDF_MAP_LPARSHORT, xts_bdf); + NPU2DBG(p, "Found LPARSHORT = 0x%x for BDF = 0x%03llx\n", id, bdf); /* Enable this mapping for both real and virtual addresses */ xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_VALID_ATRGPA0, 0UL, 1); @@ -2090,8 +2078,7 @@ static int64_t opal_npu_init_context(uint64_t phb_id, int pasid, uint64_t msr, /* Enables TLBIE/MMIOSD forwarding for this entry */ xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_VALID_ATSD, xts_bdf_pid, 1); - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_LPARSHORT, xts_bdf_pid, - lparshort); + xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_LPARSHORT, xts_bdf_pid, id); /* Set the relevant MSR bits */ xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_MSR_DR, xts_bdf_pid, @@ -2105,8 +2092,20 @@ static int64_t opal_npu_init_context(uint64_t phb_id, int pasid, uint64_t msr, * it here */ xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_MSR_SF, xts_bdf_pid, 1); - /* Finally set the PID/PASID */ - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_PASID, xts_bdf_pid, pasid); + /* + * Throw an error if the wildcard entry for this bdf is already set + * with different msr bits. + */ + old_xts_bdf_pid = npu2_read(p, NPU2_XTS_PID_MAP + id*0x20); + if (old_xts_bdf_pid) { + if (GETFIELD(NPU2_XTS_PID_MAP_MSR, old_xts_bdf_pid) != + GETFIELD(NPU2_XTS_PID_MAP_MSR, xts_bdf_pid)) { + NPU2ERR(p, "%s: Unexpected MSR value\n", __func__); + id = OPAL_PARAMETER; + } + + goto out; + } /* Write the entry */ NPU2DBG(p, "XTS_PID_MAP[%03d] = 0x%08llx\n", id, xts_bdf_pid); @@ -2118,13 +2117,13 @@ out: } opal_call(OPAL_NPU_INIT_CONTEXT, opal_npu_init_context, 4); -static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) +static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid __unused, + uint64_t bdf) { struct phb *phb = pci_get_phb(phb_id); struct npu2 *p = phb_to_npu2(phb); - uint64_t xts_bdf, xts_bdf_pid; - uint64_t lparshort; - int id, rc = 0; + uint64_t xts_bdf; + int rc = 0; if (!phb || phb->phb_type != phb_type_npu_v2) return OPAL_PARAMETER; @@ -2137,26 +2136,13 @@ static int opal_npu_destroy_context(uint64_t phb_id, uint64_t pid, uint64_t bdf) &xts_bdf, NPU2_XTS_BDF_MAP_BDF) < 0) { NPU2ERR(p, "LPARID not associated with any GPU\n"); rc = OPAL_PARAMETER; - goto out; } - lparshort = GETFIELD(NPU2_XTS_BDF_MAP_LPARSHORT, xts_bdf); - NPU2DBG(p, "Found LPARSHORT = 0x%llx destroy context for BDF = 0x%03llx PID = 0x%llx\n", - lparshort, bdf, pid); - - /* Now find the entry in the bdf/pid table */ - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_LPARSHORT, 0ul, lparshort); - xts_bdf_pid = SETFIELD(NPU2_XTS_PID_MAP_PASID, xts_bdf_pid, pid); - id = npu_table_search(p, NPU2_XTS_PID_MAP, 0x20, NPU2_XTS_PID_MAP_SIZE, &xts_bdf_pid, - NPU2_XTS_PID_MAP_LPARSHORT | NPU2_XTS_PID_MAP_PASID); - if (id < 0) { - rc = OPAL_PARAMETER; - goto out; - } + /* + * The bdf/pid table only contains wildcard entries, so we don't + * need to remove anything here. + */ - /* And zero the entry */ - npu2_write(p, NPU2_XTS_PID_MAP + id*0x20, 0); -out: unlock(&p->lock); return rc; } @@ -2208,6 +2194,7 @@ static int opal_npu_map_lpar(uint64_t phb_id, uint64_t bdf, uint64_t lparid, } xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_VALID, 0UL, 1); + xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_UNFILT, xts_bdf_lpar, 1); xts_bdf_lpar = SETFIELD(NPU2_XTS_BDF_MAP_BDF, xts_bdf_lpar, bdf); /* We only support radix for the moment */ diff --git a/include/npu2-regs.h b/include/npu2-regs.h index 73925f9..fd249f4 100644 --- a/include/npu2-regs.h +++ b/include/npu2-regs.h @@ -425,6 +425,7 @@ void npu2_write_mask(struct npu2 *p, uint64_t reg, uint64_t val, uint64_t mask); #define NPU2_XTS_MMIO_ATSD7_LPARID NPU2_REG_OFFSET(NPU2_STACK_MISC, NPU2_BLOCK_XTS, 0x138) #define NPU2_XTS_BDF_MAP NPU2_REG_OFFSET(NPU2_STACK_MISC, NPU2_BLOCK_XTS, 0x4000) #define NPU2_XTS_BDF_MAP_VALID PPC_BIT(0) +#define NPU2_XTS_BDF_MAP_UNFILT PPC_BIT(1) #define NPU2_XTS_BDF_MAP_STACK PPC_BITMASK(4, 6) #define NPU2_XTS_BDF_MAP_BRICK PPC_BIT(7) #define NPU2_XTS_BDF_MAP_BDF PPC_BITMASK(16, 31) @@ -437,6 +438,7 @@ void npu2_write_mask(struct npu2 *p, uint64_t reg, uint64_t val, uint64_t mask); #define NPU2_XTS_PID_MAP_VALID_ATRGPA0 PPC_BIT(0) #define NPU2_XTS_PID_MAP_VALID_ATRGPA1 PPC_BIT(1) #define NPU2_XTS_PID_MAP_VALID_ATSD PPC_BIT(2) +#define NPU2_XTS_PID_MAP_MSR PPC_BITMASK(25,31) #define NPU2_XTS_PID_MAP_MSR_DR PPC_BIT(25) #define NPU2_XTS_PID_MAP_MSR_TA PPC_BIT(26) #define NPU2_XTS_PID_MAP_MSR_HV PPC_BIT(27)
The XTS_PID context table is limited to 256 possible pids/contexts. To relieve this limitation, make use of "unfiltered mode" instead. If an entry in the XTS_BDF table has the bit for unfiltered mode set, we can just use one context for that entire bdf/lpar, regardless of pid. Instead of of searching the XTS_PID table, the NMMU checkout request will simply use the entry indexed by lparshort id instead. Change opal_npu_init_context() to create these lparshort-indexed wildcard entries (0-15) instead of allocating one for each pid. Check that multiple calls for the same bdf all specify the same msr value. In opal_npu_destroy_context(), continue validating the bdf argument, ensuring that it actually maps to an lpar, but no longer remove anything from the XTS_PID table. If/when we start supporting virtualized GPUs, we might consider actually removing these wildcard entries by keeping a refcount, but keep things simple for now. Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> --- hw/npu2.c | 73 ++++++++++++++++++++++------------------------------- include/npu2-regs.h | 2 ++ 2 files changed, 32 insertions(+), 43 deletions(-)