[Skiboot] [PATCH 8/8] pci: Wait 20ms before checking presence detect on PCIe

Benjamin Herrenschmidt benh at kernel.crashing.org
Tue Jun 6 08:59:24 AEST 2017


As the PHB presence logic has a debounce timer that can take
a while to settle.

Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
---
 core/pci.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/core/pci.c b/core/pci.c
index 1477358..2d3c4f8 100644
--- a/core/pci.c
+++ b/core/pci.c
@@ -1641,6 +1641,11 @@ void pci_init_slots(void)
 {
 	unsigned int i;
 
+	/* Some PHBs may need that long to debounce the presence detect
+	 * after HW initialization.
+	 */
+	time_wait_ms(20);
+
 	prlog(PR_NOTICE, "PCI: Resetting PHBs...\n");
 	pci_do_jobs(pci_reset_phb);
 
-- 
2.9.4



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