On 6/20/22 05:01, Alexey Kardashevskiy wrote:
PAPR+/LoPAPR says:
===
The platform must restore the default DMA window for the PE on a call
to the ibm,remove-pe-dma-window RTAS call when all of the following
are true:
a. The call removes the last DMA window remaining for the PE.
b. The DMA window being removed is not the default window
===
This resets DMA as PAPR mandates.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
Looks good. One comment below:
include/hw/ppc/spapr.h | 3 ++-
hw/ppc/spapr_iommu.c | 8 +++++---
hw/ppc/spapr_pci.c | 2 +-
hw/ppc/spapr_rtas_ddw.c | 17 ++++++++++++++++-
hw/ppc/spapr_vio.c | 3 ++-
5 files changed, 26 insertions(+), 7 deletions(-)
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 072dda2c7265..0adbe1566d40 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -902,6 +902,7 @@ struct SpaprTceTable {
bool bypass;
bool need_vfio;
bool skipping_replay;
+ bool def_win;
int fd;
MemoryRegion root;
IOMMUMemoryRegion iommu;
@@ -928,7 +929,7 @@ void spapr_check_mmu_mode(bool guest_radix);
SpaprTceTable *spapr_tce_new_table(DeviceState *owner, uint32_t liobn);
void spapr_tce_table_enable(SpaprTceTable *tcet,
uint32_t page_shift, uint64_t bus_offset,
- uint32_t nb_table);
+ uint32_t nb_table, bool def_win);
Do we need to add 'def_win' to spapr_tce_table_enable()? I see that you're using
the 'def_win' var to assign
+ tcet->def_win = def_win;
but the only case where def_win will be other than 'false' is:
- the function is called by spapr_tce_post_load(), but in that case it's being
callied like this:
spapr_tce_table_enable(tcet, old_page_shift, old_bus_offset,
tcet->mig_nb_table, tcet->def_win);
which results in the function doing tcet->def_win = tcet->def_win, which is
uneeded.
- the function is called by spapr_phb_dma_reset(). In this case I believe
we can just do "tcet->def_win = true" before calling spapr_tce_table_enable():
/* Register default 32bit DMA window */
tcet = spapr_tce_find_by_liobn(sphb->dma_liobn[0]);
+ tcet->def_win = true;
spapr_tce_table_enable(tcet, SPAPR_TCE_PAGE_SHIFT, sphb->dma_win_addr,
sphb->dma_win_size >> SPAPR_TCE_PAGE_SHIFT);
}
All other calls to spapr_tce_table_enable() are passing 'false' to def_win and
can be left alone.
Assuming that there's no way a created DMA window becomes the default window, or
the default DMA window is demoted to non-default, I think we can leave
spapr_tce_table_enable() untouched and just set tcet->def_win to true inside
spapr_phb_dma_reset().
Thanks,
Daniel
void spapr_tce_table_disable(SpaprTceTable *tcet);
void spapr_tce_set_need_vfio(SpaprTceTable *tcet, bool need_vfio);
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index 81e5a1aea3a6..f8c1627d0782 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -242,7 +242,7 @@ static int spapr_tce_table_post_load(void *opaque, int
version_id)
if (tcet->mig_nb_table) {
if (!tcet->nb_table) {
spapr_tce_table_enable(tcet, old_page_shift, old_bus_offset,
- tcet->mig_nb_table);
+ tcet->mig_nb_table, tcet->def_win);
}
memcpy(tcet->table, tcet->mig_table,
@@ -279,7 +279,7 @@ static const VMStateDescription vmstate_spapr_tce_table_ex
= {
static const VMStateDescription vmstate_spapr_tce_table = {
.name = "spapr_iommu",
- .version_id = 2,
+ .version_id = 3,
.minimum_version_id = 2,
.pre_save = spapr_tce_table_pre_save,
.post_load = spapr_tce_table_post_load,
@@ -292,6 +292,7 @@ static const VMStateDescription vmstate_spapr_tce_table = {
VMSTATE_BOOL(bypass, SpaprTceTable),
VMSTATE_VARRAY_UINT32_ALLOC(mig_table, SpaprTceTable, mig_nb_table, 0,
vmstate_info_uint64, uint64_t),
+ VMSTATE_BOOL_V(def_win, SpaprTceTable, 3),
VMSTATE_END_OF_LIST()
},
@@ -380,7 +381,7 @@ SpaprTceTable *spapr_tce_new_table(DeviceState *owner,
uint32_t liobn)
void spapr_tce_table_enable(SpaprTceTable *tcet,
uint32_t page_shift, uint64_t bus_offset,
- uint32_t nb_table)
+ uint32_t nb_table, bool def_win)
{
if (tcet->nb_table) {
warn_report("trying to enable already enabled TCE table");
@@ -390,6 +391,7 @@ void spapr_tce_table_enable(SpaprTceTable *tcet,
tcet->bus_offset = bus_offset;
tcet->page_shift = page_shift;
tcet->nb_table = nb_table;
+ tcet->def_win = def_win;
tcet->table = spapr_tce_alloc_table(tcet->liobn,
tcet->page_shift,
tcet->bus_offset,
diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index b2f5fbef0c83..e1dbccfc7547 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -2066,7 +2066,7 @@ void spapr_phb_dma_reset(SpaprPhbState *sphb)
/* Register default 32bit DMA window */
tcet = spapr_tce_find_by_liobn(sphb->dma_liobn[0]);
spapr_tce_table_enable(tcet, SPAPR_TCE_PAGE_SHIFT, sphb->dma_win_addr,
- sphb->dma_win_size >> SPAPR_TCE_PAGE_SHIFT);
+ sphb->dma_win_size >> SPAPR_TCE_PAGE_SHIFT, true);
}
static void spapr_phb_reset(DeviceState *qdev)
diff --git a/hw/ppc/spapr_rtas_ddw.c b/hw/ppc/spapr_rtas_ddw.c
index 13d339c807c1..4fe41b0c4539 100644
--- a/hw/ppc/spapr_rtas_ddw.c
+++ b/hw/ppc/spapr_rtas_ddw.c
@@ -182,7 +182,7 @@ static void rtas_ibm_create_pe_dma_window(PowerPCCPU *cpu,
*/
tcet->skipping_replay = true;
spapr_tce_table_enable(tcet, page_shift, win_addr,
- 1ULL << (window_shift - page_shift));
+ 1ULL << (window_shift - page_shift), false);
tcet->skipping_replay = false;
if (!tcet->nb_table) {
goto hw_error_exit;
@@ -215,6 +215,7 @@ static void rtas_ibm_remove_pe_dma_window(PowerPCCPU *cpu,
SpaprPhbState *sphb;
SpaprTceTable *tcet;
uint32_t liobn;
+ bool def_win_removed;
if ((nargs != 1) || (nret != 1)) {
goto param_error_exit;
@@ -231,9 +232,23 @@ static void rtas_ibm_remove_pe_dma_window(PowerPCCPU *cpu,
goto param_error_exit;
}
+ def_win_removed = tcet->def_win;
spapr_tce_table_disable(tcet);
trace_spapr_iommu_ddw_remove(liobn);
+ /*
+ * PAPR+/LoPAPR says:
+ * The platform must restore the default DMA window for the PE on a call
+ * to the ibm,remove-pe-dma-window RTAS call when all of the following
+ * are true:
+ * a. The call removes the last DMA window remaining for the PE.
+ * b. The DMA window being removed is not the default window
+ */
+ if (spapr_phb_get_active_win_num(sphb) == 0 && !def_win_removed) {
+ spapr_phb_dma_reset(sphb);
+ trace_spapr_iommu_ddw_reset(sphb->buid, 0);
+ }
+
rtas_st(rets, 0, RTAS_OUT_SUCCESS);
return;
diff --git a/hw/ppc/spapr_vio.c b/hw/ppc/spapr_vio.c
index 9d4fec2c04d8..14506df19d62 100644
--- a/hw/ppc/spapr_vio.c
+++ b/hw/ppc/spapr_vio.c
@@ -533,7 +533,8 @@ static void spapr_vio_busdev_realize(DeviceState *qdev,
Error **errp)
dev->tcet = spapr_tce_new_table(qdev, liobn);
spapr_tce_table_enable(dev->tcet, SPAPR_TCE_PAGE_SHIFT, 0,
- pc->rtce_window_size >> SPAPR_TCE_PAGE_SHIFT);
+ pc->rtce_window_size >> SPAPR_TCE_PAGE_SHIFT,
+ false);
dev->tcet->vdev = dev;
memory_region_add_subregion_overlap(&dev->mrroot, 0,
spapr_tce_get_iommu(dev->tcet),
2);
