[Skiboot] [PATCH 3/8] phb3: Turn the link speed hack into a cfg filter

[Benjamin Herrenschmidt]

Rather than special casing it openly.

Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
---
 hw/phb3.c | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/hw/phb3.c b/hw/phb3.c
index f32142e..e761cfe 100644
--- a/hw/phb3.c
+++ b/hw/phb3.c
@@ -216,26 +216,36 @@ static void phb3_link_update(struct phb *phb, uint16_t data)
 	}
 }
 
-static int64_t phb3_pcicfg_filter(struct phb *phb, uint32_t bdfn,
-				  uint32_t offset, uint32_t len,
-				  uint32_t *data, bool write)
+static int64_t phb3_pcicfg_rc_link_speed(void *dev,
+					 struct pci_cfg_reg_filter *pcrf __unused,
+					 uint32_t offset, uint32_t len,
+					 uint32_t *data,  bool write)
 {
-	struct pci_device *pd;
-	struct pci_cfg_reg_filter *pcrf;
-	uint32_t flags;
+	struct pci_device *pd = dev;
 
 	/* Hack for link speed changes. We intercept attempts at writing
 	 * the link control/status register
 	 */
-	if (bdfn == 0 && write && len == 4 && offset == 0x58) {
-		phb3_link_update(phb, (*data) >> 16);
+	if (write && len == 4 && offset == 0x58) {
+		phb3_link_update(pd->phb, (*data) >> 16);
 		return OPAL_SUCCESS;
 	}
-	if (bdfn == 0 && write && len == 2 && offset == 0x5a) {
-		phb3_link_update(phb, *(uint16_t *)data);
+	if (write && len == 2 && offset == 0x5a) {
+		phb3_link_update(pd->phb, *(uint16_t *)data);
 		return OPAL_SUCCESS;
 	}
 
+	return OPAL_PARTIAL;
+}
+
+static int64_t phb3_pcicfg_filter(struct phb *phb, uint32_t bdfn,
+				  uint32_t offset, uint32_t len,
+				  uint32_t *data, bool write)
+{
+	struct pci_device *pd;
+	struct pci_cfg_reg_filter *pcrf;
+	uint32_t flags;
+
 	if (!pci_device_has_cfg_reg_filters(phb, bdfn))
 		return OPAL_PARTIAL;
 	pd = pci_find_dev(phb, bdfn);
@@ -636,6 +646,11 @@ static void phb3_check_device_quirks(struct phb *phb, struct pci_device *dev)
 					PCI_CFG_PREF_MEM_BASE_U32, 12,
 					PCI_REG_FLAG_READ | PCI_REG_FLAG_WRITE,
 					phb3_pcicfg_rc_pref_window);
+			/* Add filter to control link speed */
+			pci_add_cfg_reg_filter(dev,
+					       0x58, 4,
+					       PCI_REG_FLAG_WRITE,
+					       phb3_pcicfg_rc_link_speed);
 		}
 	}
 }
-- 
2.9.4