On Sun, May 10, 2015 at 12:30:07AM +1000, Alexey Kardashevskiy wrote:
>On 05/01/2015 04:03 PM, Gavin Shan wrote:
>>We might not get some PCI slot information (e.g. power status)
>>immediately by OPAL API. Instead, opal_pci_poll() need to be called
>>for the required information.
>>
>>The patch introduces pnv_pci_poll(), which bases on original
>>pnv_eeh_poll(), to cover the above case
>>
>>Signed-off-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>
>>---
>> arch/powerpc/platforms/powernv/eeh-powernv.c | 28 ++--------------------------
>> arch/powerpc/platforms/powernv/pci.c | 16 ++++++++++++++++
>> arch/powerpc/platforms/powernv/pci.h | 1 +
>> 3 files changed, 19 insertions(+), 26 deletions(-)
>>
>>diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
>>index 58e4dcf..9253b9e 100644
>>--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
>>+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
>>@@ -742,24 +742,6 @@ static int pnv_eeh_get_state(struct eeh_pe *pe, int *delay)
>> return ret;
>> }
>>
>>-static s64 pnv_eeh_poll(uint64_t id)
>>-{
>>- s64 rc = OPAL_HARDWARE;
>>-
>>- while (1) {
>>- rc = opal_pci_poll(id, NULL);
>>- if (rc <= 0)
>>- break;
>>-
>>- if (system_state < SYSTEM_RUNNING)
>>- udelay(1000 * rc);
>>- else
>>- msleep(rc);
>>- }
>>-
>>- return rc;
>>-}
>>-
>> int pnv_eeh_phb_reset(struct pci_controller *hose, int option)
>> {
>> struct pnv_phb *phb = hose->private_data;
>>@@ -788,10 +770,7 @@ int pnv_eeh_phb_reset(struct pci_controller *hose, int option)
>>
>> /* Issue reset and poll until it's completed */
>> rc = opal_pci_reset(phb->opal_id, scope, OPAL_ASSERT_RESET);
>>- if (rc > 0)
>>- rc = pnv_eeh_poll(phb->opal_id);
>>-
>>- return (rc == OPAL_SUCCESS) ? 0 : -EIO;
>>+ return pnv_pci_poll(phb->opal_id, rc, NULL);
>
>
>You are carrying a negative value to the new helper too? Looks complicated.
>
Yes, a bit complicated :-)
>Also, before you only cared if opal_pci_reset() returned negative value, now
>you treat it as a timeout, is it new change to OPAL or it has always been
>there?
>
No, I didn't change the behaviour from skiboot side. The function should
have following return values:
0 - success; <0 - Error; >0 - Delay in ms;
>
>> }
>>
>> static int __pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
>>@@ -882,10 +861,7 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
>> phb = hose->private_data;
>> id |= (dev->bus->number << 24) | (dev->devfn << 16) | phb->opal_id;
>> rc = opal_pci_reset(id, scope, OPAL_ASSERT_RESET);
>>- if (rc > 0)
>>- rc = pnv_eeh_poll(id);
>>-
>>- return (rc == OPAL_SUCCESS) ? 0 : -EIO;
>>+ return pnv_pci_poll(id, rc, NULL);
>> }
>>
>> static int pnv_pci_dev_reset_type(struct pci_dev *pdev, void *data)
>>diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
>>index bca2aeb..a2da9a3 100644
>>--- a/arch/powerpc/platforms/powernv/pci.c
>>+++ b/arch/powerpc/platforms/powernv/pci.c
>>@@ -44,6 +44,22 @@
>> #define cfg_dbg(fmt...) do { } while(0)
>> //#define cfg_dbg(fmt...) printk(fmt)
>>
>>+int pnv_pci_poll(uint64_t id, int64_t rval, uint8_t *pval)
>>+{
>>+ while (rval > 0) {
>>+ if (system_state < SYSTEM_RUNNING)
>>+ udelay(1000 * rval);
>>+ else
>>+ msleep(rval);
>
>Are these delays the once removed by "PATCH v4 09/21] powerpc/powernv: Use
>PCI slot reset infrastructure"? If so, I would merge this patch into 09/24 or
>move this one before that one, for bisect'ability.
>
No, they are different. The delay here is expected from skiboot firmware, but
that one in "PATCH v4 09/21" is expected from kernel itself.
>
>>+
>>+ rval = opal_pci_poll(id, pval);
>>+ if (rval == OPAL_SUCCESS && pval)
>>+ rval = opal_pci_poll(id, pval);
>
>Why calling it twice?
>
When retrieving slot's presence or power status, we have to do so as the opal_pci_poll()
is implemented like that. It means the first OPAL_SUCCESS from opal_pci_poll() indicates
the state machine, by which the function is implemented has finished. The next call to
the same function will get the result.
>>+ }
>>+
>>+ return rval ? -EIO : 0;
>>+}
>>+
>> #ifdef CONFIG_PCI_MSI
>> static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
>> {
>>diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
>>index 8b10f01..82c5539 100644
>>--- a/arch/powerpc/platforms/powernv/pci.h
>>+++ b/arch/powerpc/platforms/powernv/pci.h
>>@@ -202,6 +202,7 @@ struct pnv_phb {
>>
>> extern struct pci_ops pnv_pci_ops;
>>
>>+int pnv_pci_poll(uint64_t id, int64_t rval, uint8_t *pval);
>> void pnv_pci_dump_phb_diag_data(struct pci_controller *hose,
>> unsigned char *log_buff);
>> int pnv_pci_cfg_read(struct pci_dn *pdn,
>>
Thanks,
Gavin
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
