path: root/drivers/misc/cxl/api.c
diff options
authorIan Munsie <imunsie@au1.ibm.com>2016-05-24 02:14:05 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2016-06-16 23:08:49 +1000
commit292841b09648ce7aee5df16ab72581f3b6c2bd7a (patch)
tree1da803196a927f5c4ecc54cb9d6724c0ece274bf /drivers/misc/cxl/api.c
parent64417a398973d964139306c0b152536e468bf77c (diff)
cxl: Update process element after allocating interrupts
In the kernel API, it is possible to attempt to allocate AFU interrupts after already starting a context. Since the process element structure used by the hardware is only filled out at the time the context is started, it will not be updated with the interrupt numbers that have just been allocated and therefore AFU interrupts will not work unless they were allocated prior to starting the context. This can present some difficulties as each CAPI enabled PCI device in the kernel API has a default context, which may need to be started very early to enable translations, potentially before interrupts can easily be set up. This patch makes the API more flexible to allow interrupts to be allocated after a context has already been started and takes care of updating the PE structure used by the hardware and notifying it to discard any cached copy it may have. The update is currently performed via a terminate/remove/add sequence. This is necessary on some hardware such as the XSL that does not properly support the update LLCMD. Note that this is only supported on powernv at present - attempting to perform this ordering on PowerVM will raise a warning. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers/misc/cxl/api.c')
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/misc/cxl/api.c b/drivers/misc/cxl/api.c
index 6d228ccd884d..99081b821f12 100644
--- a/drivers/misc/cxl/api.c
+++ b/drivers/misc/cxl/api.c
@@ -102,7 +102,10 @@ int cxl_allocate_afu_irqs(struct cxl_context *ctx, int num)
if (num == 0)
num = ctx->afu->pp_irqs;
res = afu_allocate_irqs(ctx, num);
- if (!res && !cpu_has_feature(CPU_FTR_HVMODE)) {
+ if (res)
+ return res;
+ if (!cpu_has_feature(CPU_FTR_HVMODE)) {
/* In a guest, the PSL interrupt is not multiplexed. It was
* allocated above, and we need to set its handler
@@ -110,6 +113,13 @@ int cxl_allocate_afu_irqs(struct cxl_context *ctx, int num)
if (hwirq)
cxl_map_irq(ctx->afu->adapter, hwirq, cxl_ops->psl_interrupt, ctx, "psl");
+ if (ctx->status == STARTED) {
+ if (cxl_ops->update_ivtes)
+ cxl_ops->update_ivtes(ctx);
+ else WARN(1, "BUG: cxl_allocate_afu_irqs must be called prior to starting the context on this platform\n");
+ }
return res;