cxl: Export library to support IBM XSL
This patch exports a in-kernel 'library' API which can be called by
other drivers to help interacting with an IBM XSL on a POWER9 system.
The XSL (Translation Service Layer) is a stripped down version of the
PSL (Power Service Layer) used in some cards such as the Mellanox CX5.
Like the PSL, it implements the CAIA architecture, but has a number
of differences, mostly in it's implementation dependent registers.
The XSL also uses a special DMA cxl mode, which uses a slightly
different init sequence for the CAPP and PHB.
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index c79e39b..6eed7d0 100644
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -132,18 +132,15 @@ static int cxl_handle_segment_miss(struct cxl_context *ctx,
return IRQ_HANDLED;
}
-static void cxl_handle_page_fault(struct cxl_context *ctx,
- struct mm_struct *mm, u64 dsisr, u64 dar)
+int cxl_handle_mm_fault(struct mm_struct *mm, u64 dsisr, u64 dar)
{
unsigned flt = 0;
int result;
unsigned long access, flags, inv_flags = 0;
- trace_cxl_pte_miss(ctx, dsisr, dar);
-
if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
pr_devel("copro_handle_mm_fault failed: %#x\n", result);
- return cxl_ack_ae(ctx);
+ return result;
}
if (!radix_enabled()) {
@@ -155,9 +152,8 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
if (dsisr & CXL_PSL_DSISR_An_S)
access |= _PAGE_WRITE;
- access |= _PAGE_PRIVILEGED;
- if ((!ctx->kernel) || (REGION_ID(dar) == USER_REGION_ID))
- access &= ~_PAGE_PRIVILEGED;
+ if (!mm && (REGION_ID(dar) != USER_REGION_ID))
+ access |= _PAGE_PRIVILEGED;
if (dsisr & DSISR_NOHPTE)
inv_flags |= HPTE_NOHPTE_UPDATE;
@@ -166,8 +162,21 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
hash_page_mm(mm, dar, access, 0x300, inv_flags);
local_irq_restore(flags);
}
- pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
- cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+ return 0;
+}
+
+static void cxl_handle_page_fault(struct cxl_context *ctx,
+ struct mm_struct *mm,
+ u64 dsisr, u64 dar)
+{
+ trace_cxl_pte_miss(ctx, dsisr, dar);
+
+ if (cxl_handle_mm_fault(mm, dsisr, dar)) {
+ cxl_ack_ae(ctx);
+ } else {
+ pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
+ cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+ }
}
/*