Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxx> writes:
> Arto Merilainen <amerilainen@xxxxxxxxxx> writes:
>
>> On 8.8.2025 20.26, dan.j.williams@xxxxxxxxx wrote:
>>> Arto Merilainen wrote:
>>>> The first revision of this patch had address association register
>>>> programming but it has since been removed. Could you comment if there is
>>>> a reason for this change?
>>>
>>> We chatted about it around this point in the original review thread [1].
>>> tl;dr SEV-TIO and TDX Connect did not see a strict need for it. However,
>>> the expectation was always to circle back and revive it if it turned out
>>> later to be required.
>>
>> Thank you for the reference. I suppose it is ok to rely on the default
>> streams on the first iteration, and add a follow-up patch in the ARM CCA
>> device assignment support series in case it is the only architecture
>> that depends on them.
>>
>>>
>>>> Some background: This might be problematic for ARM CCA. I recall seeing
>>>> a comment stating that the address association register programming can
>>>> be skipped on some architectures (e.g., apparently AMD uses a separate
>>>> table that contains the StreamID) but on ARM CCA the StreamID
>>>> association AFAIK happens through these registers.
>>>
>>> Can you confirm and perhaps work with Aneesh to propose an incremental
>>> patch to add that support back? It might be something that we let the
>>> low level TSM driver control. Like an additional address association
>>> object that can be attached to 'struct pci_ide' by the low level TSM
>>> driver.
>>
>> Aneesh, could you perhaps extend the IDE driver by adding the RP address
>> association register programming in the next revision of the DA support
>> series?
>>
>
> Sure, I can add that change as part of next update.
>
This is the change I am adding
drivers/pci/ide.c | 128 ++++++++++++++++++++++-
drivers/virt/coco/arm-cca-host/arm-cca.c | 13 +++
include/linux/pci-ide.h | 7 ++
3 files changed, 147 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c
index 3f772979eacb..23d1712ba97a 100644
--- a/drivers/pci/ide.c
+++ b/drivers/pci/ide.c
@@ -101,7 +101,7 @@ void pci_ide_init(struct pci_dev *pdev)
pdev->ide_cap = ide_cap;
pdev->nr_link_ide = nr_link_ide;
pdev->nr_sel_ide = nr_streams;
- pdev->nr_ide_mem = nr_ide_mem;
+ pdev->nr_ide_mem = min(nr_ide_mem, PCI_IDE_AASOC_REG_MAX);
}
struct stream_index {
@@ -213,11 +213,13 @@ struct pci_ide *pci_ide_stream_alloc(struct pci_dev *pdev)
.rid_start = pci_dev_id(rp),
.rid_end = pci_dev_id(rp),
.stream_index = no_free_ptr(ep_stream)->stream_index,
+ .nr_mem = 0,
},
[PCI_IDE_RP] = {
.rid_start = pci_dev_id(pdev),
.rid_end = rid_end,
.stream_index = no_free_ptr(rp_stream)->stream_index,
+ .nr_mem = 0,
},
},
.host_bridge_stream = no_free_ptr(hb_stream)->stream_index,
@@ -228,6 +230,109 @@ struct pci_ide *pci_ide_stream_alloc(struct pci_dev *pdev)
}
EXPORT_SYMBOL_GPL(pci_ide_stream_alloc);
+static int add_range_merge_overlap(struct range *range, int az, int nr_range,
+ u64 start, u64 end)
+{
+ int i;
+
+ if (start >= end)
+ return nr_range;
+
+ /* get new start/end: */
+ for (i = 0; i < nr_range; i++) {
+
+ if (!range[i].end)
+ continue;
+
+ /* Try to add to the end */
+ if (range[i].end + 1 == start) {
+ range[i].end = end;
+ return nr_range;
+ }
+
+ /* Try to add to the start */
+ if (range[i].start == end + 1) {
+ range[i].start = start;
+ return nr_range;
+ }
+ }
+
+ /* Need to add it: */
+ return add_range(range, az, nr_range, start, end);
+}
+
+int pci_ide_add_address_assoc_block(struct pci_dev *pdev,
+ struct pci_ide *ide,
+ u64 start, u64 end)
+{
+ struct pci_ide_partner *partner;
+
+ if (!pci_is_pcie(pdev)) {
+ pci_warn_once(pdev, "not a PCIe device\n");
+ return -EINVAL;
+ }
+
+ switch (pci_pcie_type(pdev)) {
+ case PCI_EXP_TYPE_ENDPOINT:
+
+ if (pdev != ide->pdev)
+ return -EINVAL;
+ partner = &ide->partner[PCI_IDE_RP];
+ break;
+ default:
+ pci_warn_once(pdev, "invalid device type\n");
+ return -EINVAL;
+ }
+
+ if (partner->nr_mem >= pdev->nr_ide_mem)
+ return -ENOMEM;
+
+ partner->nr_mem = add_range_merge_overlap(partner->mem,
+ PCI_IDE_AASOC_REG_MAX, partner->nr_mem,
+ start, end);
+ return 0;
+}
+
+
+int pci_ide_merge_address_assoc_block(struct pci_dev *pdev,
+ struct pci_ide *ide, u64 start, u64 end)
+{
+ struct pci_ide_partner *partner;
+
+ if (!pci_is_pcie(pdev)) {
+ pci_warn_once(pdev, "not a PCIe device\n");
+ return -EINVAL;
+ }
+
+ switch (pci_pcie_type(pdev)) {
+ case PCI_EXP_TYPE_ENDPOINT:
+
+ if (pdev != ide->pdev)
+ return -EINVAL;
+ partner = &ide->partner[PCI_IDE_RP];
+ break;
+ default:
+ pci_warn_once(pdev, "invalid device type\n");
+ return -EINVAL;
+ }
+
+ for (int i = 0; i < PCI_IDE_AASOC_REG_MAX; i++) {
+ struct range *r = &partner->mem[i];
+
+ if (r->start < start)
+ start = r->start;
+ if (r->end > end)
+ end = r->end;
+ r->start = 0;
+ r->end = 0;
+ }
+ partner->mem[0].start = start;
+ partner->mem[0].end = end;
+ partner->nr_mem = 1;
+
+ return 0;
+}
+
/**
* pci_ide_stream_free() - unwind pci_ide_stream_alloc()
* @ide: idle IDE settings descriptor
@@ -424,6 +529,21 @@ void pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, val);
+ for (int i = 0; i < settings->nr_mem; i++) {
+ val = FIELD_PREP(PCI_IDE_SEL_ADDR_1_VALID, 1) |
+ FIELD_PREP(PCI_IDE_SEL_ADDR_1_BASE_LOW,
+ lower_32_bits(settings->mem[i].start)) |
+ FIELD_PREP(PCI_IDE_SEL_ADDR_1_LIMIT_LOW,
+ lower_32_bits(settings->mem[i].end));
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), val);
+
+ val = upper_32_bits(settings->mem[i].end);
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), val);
+
+ val = upper_32_bits(settings->mem[i].start);
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), val);
+ }
+
/*
* Setup control register early for devices that expect
* stream_id is set during key programming.
@@ -453,6 +573,12 @@ void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide)
pos = sel_ide_offset(pdev, settings);
pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, 0);
+ for (int i = settings->nr_mem - 1; i >= 0; i--) {
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), 0);
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), 0);
+ pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), 0);
+ }
+
pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, 0);
pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, 0);
settings->setup = 0;
diff --git a/drivers/virt/coco/arm-cca-host/arm-cca.c b/drivers/virt/coco/arm-cca-host/arm-cca.c
index c9717698af56..28993f9277e4 100644
--- a/drivers/virt/coco/arm-cca-host/arm-cca.c
+++ b/drivers/virt/coco/arm-cca-host/arm-cca.c
@@ -137,6 +137,7 @@ static int cca_tsm_connect(struct pci_dev *pdev)
{
struct pci_dev *rp = pcie_find_root_port(pdev);
struct cca_host_pf0_dsc *dsc_pf0;
+ struct resource *res;
struct pci_ide *ide;
int rc, stream_id;
@@ -163,9 +164,21 @@ static int cca_tsm_connect(struct pci_dev *pdev)
if (rc)
goto err_stream;
+ /*
+ * Try to use the available address assoc register blocks.
+ * If we fail with ENOMEM, create one block covering the entire
+ * address range. (Should work for arm64)
+ */
+ pci_dev_for_each_resource(pdev, res) {
+ rc = pci_ide_add_address_assoc_block(pdev, ide, res->start, res->end);
+ if (rc == -ENOMEM)
+ pci_ide_merge_address_assoc_block(pdev, ide, res->start, res->end);
+ }
+
pci_ide_stream_setup(pdev, ide);
pci_ide_stream_setup(rp, ide);
+
rc = tsm_ide_stream_register(ide);
if (rc)
goto err_tsm;
diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h
index c3838d11af88..3d4f7f462a8d 100644
--- a/include/linux/pci-ide.h
+++ b/include/linux/pci-ide.h
@@ -19,6 +19,7 @@ enum pci_ide_partner_select {
PCI_IDE_HB = PCI_IDE_PARTNER_MAX,
};
+#define PCI_IDE_AASOC_REG_MAX 6
/**
* struct pci_ide_partner - Per port pair Selective IDE Stream settings
* @rid_start: Partner Port Requester ID range start
@@ -34,6 +35,8 @@ struct pci_ide_partner {
u8 stream_index;
unsigned int setup:1;
unsigned int enable:1;
+ int nr_mem;
+ struct range mem[PCI_IDE_AASOC_REG_MAX];
};
/**
@@ -60,6 +63,10 @@ struct pci_ide {
struct pci_ide_partner *pci_ide_to_settings(struct pci_dev *pdev, struct pci_ide *ide);
struct pci_ide *pci_ide_stream_alloc(struct pci_dev *pdev);
+int pci_ide_add_address_assoc_block(struct pci_dev *pdev,
+ struct pci_ide *ide, u64 start, u64 end);
+int pci_ide_merge_address_assoc_block(struct pci_dev *pdev,
+ struct pci_ide *ide, u64 start, u64 end);
void pci_ide_stream_free(struct pci_ide *ide);
int pci_ide_stream_register(struct pci_ide *ide);
void pci_ide_stream_unregister(struct pci_ide *ide);
--
2.43.0
