[U-Boot] [PATCH 1/6] pci: Set PCI_COMMAND_IO bit for VGA device

Bin Meng bmeng.cn at gmail.com
Thu Oct 1 09:35:59 CEST 2015


PCI_COMMAND_IO bit must be set for VGA device as it needs to respond
to legacy VGA IO address.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 drivers/pci/pci_auto.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
index 41d5447..e2c239e 100644
--- a/drivers/pci/pci_auto.c
+++ b/drivers/pci/pci_auto.c
@@ -89,6 +89,7 @@ void pciauto_setup_device(struct pci_controller *hose,
 	struct pci_region *bar_res;
 	int found_mem64 = 0;
 #endif
+	u16 class;
 
 	pci_hose_read_config_word(hose, dev, PCI_COMMAND, &cmdstat);
 	cmdstat = (cmdstat & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) | PCI_COMMAND_MASTER;
@@ -205,6 +206,11 @@ void pciauto_setup_device(struct pci_controller *hose,
 	}
 #endif
 
+	/* PCI_COMMAND_IO must be set for VGA device */
+	pci_hose_read_config_word(hose, dev, PCI_CLASS_DEVICE, &class);
+	if (class == PCI_CLASS_DISPLAY_VGA)
+		cmdstat |= PCI_COMMAND_IO;
+
 	pci_hose_write_config_word(hose, dev, PCI_COMMAND, cmdstat);
 	pci_hose_write_config_byte(hose, dev, PCI_CACHE_LINE_SIZE,
 		CONFIG_SYS_PCI_CACHE_LINE_SIZE);
-- 
1.8.2.1



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