ocxl: Update the Process Element Entry

To complete the MMIO based mechanism, the fields: PASID, bus, device and
function of the Process Element Entry have to be filled. (See
OpenCAPI Power Platform Architecture document)

                   Hypervisor Process Element Entry
Word
    0 1 .... 7  8  ...... 12  13 ..15  16.... 19  20 ........... 31
0                  OSL Configuration State (0:31)
1                  OSL Configuration State (32:63)
2               PASID                      |    Reserved
3       Bus   |   Device    |Function |        Reserved
4                             Reserved
5                             Reserved
6                               ....

Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201125155013.39955-4-clombard@linux.vnet.ibm.com

drivers/misc/ocxl/context.c

@@ -70,6 +70,7 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr, struct mm_struct *mm)
 {
 	int rc;
 	unsigned long pidr = 0;
+	struct pci_dev *dev;
 
 	// Locks both status & tidr
 	mutex_lock(&ctx->status_mutex);
@@ -81,8 +82,9 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr, struct mm_struct *mm)
 	if (mm)
 		pidr = mm->context.id;
 
+	dev = to_pci_dev(ctx->afu->fn->dev.parent);
 	rc = ocxl_link_add_pe(ctx->afu->fn->link, ctx->pasid, pidr, ctx->tidr,
-			      amr, mm, xsl_fault_error, ctx);
+			      amr, pci_dev_id(dev), mm, xsl_fault_error, ctx);
 	if (rc)
 		goto out;
 

drivers/misc/ocxl/link.c

@@ -494,7 +494,7 @@ static u64 calculate_cfg_state(bool kernel)
 }
 
 int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
-		u64 amr, struct mm_struct *mm,
+		u64 amr, u16 bdf, struct mm_struct *mm,
 		void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr),
 		void *xsl_err_data)
 {
@@ -529,6 +529,8 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
 
 	memset(pe, 0, sizeof(struct ocxl_process_element));
 	pe->config_state = cpu_to_be64(calculate_cfg_state(pidr == 0));
+	pe->pasid = cpu_to_be32(pasid << (31 - 19));
+	pe->bdf = cpu_to_be16(bdf);
 	pe->lpid = cpu_to_be32(mfspr(SPRN_LPID));
 	pe->pid = cpu_to_be32(pidr);
 	pe->tid = cpu_to_be32(tidr);

drivers/misc/ocxl/ocxl_internal.h

@@ -84,13 +84,16 @@ struct ocxl_context {
 
 struct ocxl_process_element {
 	__be64 config_state;
-	__be32 reserved1[11];
+	__be32 pasid;
+	__be16 bdf;
+	__be16 reserved1;
+	__be32 reserved2[9];
 	__be32 lpid;
 	__be32 tid;
 	__be32 pid;
-	__be32 reserved2[10];
+	__be32 reserved3[10];
 	__be64 amr;
-	__be32 reserved3[3];
+	__be32 reserved4[3];
 	__be32 software_state;
 };
 

drivers/scsi/cxlflash/ocxl_hw.c

@@ -329,6 +329,7 @@ static int start_context(struct ocxlflash_context *ctx)
 	struct ocxl_hw_afu *afu = ctx->hw_afu;
 	struct ocxl_afu_config *acfg = &afu->acfg;
 	void *link_token = afu->link_token;
+	struct pci_dev *pdev = afu->pdev;
 	struct device *dev = afu->dev;
 	bool master = ctx->master;
 	struct mm_struct *mm;
@@ -360,8 +361,9 @@ static int start_context(struct ocxlflash_context *ctx)
 		mm = current->mm;
 	}
 
-	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0, mm,
-			      ocxlflash_xsl_fault, ctx);
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0,
+			      pci_dev_id(pdev), mm, ocxlflash_xsl_fault,
+			      ctx);
 	if (unlikely(rc)) {
 		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
 			__func__, rc);

include/misc/ocxl.h

@@ -447,7 +447,7 @@ void ocxl_link_release(struct pci_dev *dev, void *link_handle);
  * defined
  */
 int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
-		u64 amr, struct mm_struct *mm,
+		u64 amr, u16 bdf, struct mm_struct *mm,
 		void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr),
 		void *xsl_err_data);