src: Never set ISA Enable on PCI bridges

Looks like no one really knows what this bit would be useful for, nor
when it would need to be set. Especially if coreboot is setting it even
on PCI *Express* bridges. Digging through git history, nearly all
instances of setting it on PCIe bridges comes from i82801gx, for which
no reason was given as to why this would be needed. The other instances
in Intel code seem to have been, unsurprisingly, copy-pasted.

Drop all uses of this definition and rename it to avoid confusion. The
negation in the name could trick people into setting this bit again.

Tested on Asrock B85M Pro4, no visible difference.

Change-Id: Ifaff29561769c111fb7897e95dbea842faec5df4
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43775
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
diff --git a/src/device/cardbus_device.c b/src/device/cardbus_device.c
index 266e194..b014946 100644
--- a/src/device/cardbus_device.c
+++ b/src/device/cardbus_device.c
@@ -119,7 +119,6 @@
 
 	ctrl = pci_read_config16(dev, PCI_CB_BRIDGE_CONTROL);
 	ctrl |= (dev->link_list->bridge_ctrl & (
-			PCI_BRIDGE_CTL_NO_ISA |
 			PCI_BRIDGE_CTL_VGA |
 			PCI_BRIDGE_CTL_MASTER_ABORT |
 			PCI_BRIDGE_CTL_BUS_RESET));
diff --git a/src/include/device/pci_def.h b/src/include/device/pci_def.h
index 07ba4a2..25372bf 100644
--- a/src/include/device/pci_def.h
+++ b/src/include/device/pci_def.h
@@ -136,7 +136,7 @@
 /* Enable parity detection on secondary interface */
 #define  PCI_BRIDGE_CTL_PARITY	0x01
 #define  PCI_BRIDGE_CTL_SERR	0x02	/* The same for SERR forwarding */
-#define  PCI_BRIDGE_CTL_NO_ISA	0x04	/* Disable bridging of ISA ports */
+#define  PCI_BRIDGE_CTL_ISA	0x04	/* Disable bridging of ISA ports */
 #define  PCI_BRIDGE_CTL_VGA	0x08	/* Forward VGA addresses */
 #define  PCI_BRIDGE_CTL_VGA16	0x10	/* Enable 16-bit i/o port decoding */
 #define  PCI_BRIDGE_CTL_MASTER_ABORT 0x20  /* Report master aborts */
diff --git a/src/soc/intel/broadwell/pcie.c b/src/soc/intel/broadwell/pcie.c
index 14dcd3f..00a8595 100644
--- a/src/soc/intel/broadwell/pcie.c
+++ b/src/soc/intel/broadwell/pcie.c
@@ -587,7 +587,6 @@
 
 	reg16 = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
 	reg16 &= ~PCI_BRIDGE_CTL_PARITY;
-	reg16 |= PCI_BRIDGE_CTL_NO_ISA;
 	pci_write_config16(dev, PCI_BRIDGE_CONTROL, reg16);
 
 	/* Clear errors in status registers */
diff --git a/src/soc/intel/common/block/pcie/pcie.c b/src/soc/intel/common/block/pcie/pcie.c
index f36366a..ada380e 100644
--- a/src/soc/intel/common/block/pcie/pcie.c
+++ b/src/soc/intel/common/block/pcie/pcie.c
@@ -24,9 +24,8 @@
 	/* Set Cache Line Size to 0x10 */
 	pci_write_config8(dev, PCI_CACHE_LINE_SIZE, CACHE_LINE_SIZE);
 
-	/* disable parity error response, enable ISA */
-	pci_update_config16(dev, PCI_BRIDGE_CONTROL,
-			    ~PCI_BRIDGE_CTL_PARITY, PCI_BRIDGE_CTL_NO_ISA);
+	/* disable parity error response */
+	pci_and_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY);
 
 	if (CONFIG(PCIE_DEBUG_INFO)) {
 		printk(BIOS_SPEW, "    MBL    = 0x%08x\n",
diff --git a/src/southbridge/intel/bd82x6x/pcie.c b/src/southbridge/intel/bd82x6x/pcie.c
index 2eff162..f6bffbb 100644
--- a/src/southbridge/intel/bd82x6x/pcie.c
+++ b/src/southbridge/intel/bd82x6x/pcie.c
@@ -216,8 +216,7 @@
 	// This has no effect but the OS might expect it
 	pci_write_config8(dev, 0x0c, 0x10);
 
-	pci_update_config16(dev, PCI_BRIDGE_CONTROL,
-			    ~PCI_BRIDGE_CTL_PARITY, PCI_BRIDGE_CTL_NO_ISA);
+	pci_and_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY);
 
 	/* Clear errors in status registers. FIXME: Do something? */
 	reg16 = pci_read_config16(dev, 0x06);
diff --git a/src/southbridge/intel/i82801gx/pcie.c b/src/southbridge/intel/i82801gx/pcie.c
index 6c0ca5d..ca0ae2e 100644
--- a/src/southbridge/intel/i82801gx/pcie.c
+++ b/src/southbridge/intel/i82801gx/pcie.c
@@ -54,7 +54,6 @@
 
 	reg16 = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
 	reg16 &= ~PCI_BRIDGE_CTL_PARITY;
-	reg16 |= PCI_BRIDGE_CTL_NO_ISA;
 	pci_write_config16(dev, PCI_BRIDGE_CONTROL, reg16);
 
 	/* Enable IO xAPIC on this PCIe port */
diff --git a/src/southbridge/intel/i82801ix/pcie.c b/src/southbridge/intel/i82801ix/pcie.c
index a8e7b11..3900e92 100644
--- a/src/southbridge/intel/i82801ix/pcie.c
+++ b/src/southbridge/intel/i82801ix/pcie.c
@@ -23,8 +23,7 @@
 	// This has no effect but the OS might expect it
 	pci_write_config8(dev, 0x0c, 0x10);
 
-	pci_update_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY,
-			    PCI_BRIDGE_CTL_NO_ISA);
+	pci_and_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY);
 
 	/* Enable IO xAPIC on this PCIe port */
 	pci_or_config32(dev, 0xd8, 1 << 7);
diff --git a/src/southbridge/intel/i82801jx/pcie.c b/src/southbridge/intel/i82801jx/pcie.c
index 5195522..18d2c72 100644
--- a/src/southbridge/intel/i82801jx/pcie.c
+++ b/src/southbridge/intel/i82801jx/pcie.c
@@ -23,8 +23,7 @@
 	// This has no effect but the OS might expect it
 	pci_write_config8(dev, 0x0c, 0x10);
 
-	pci_update_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY,
-			    PCI_BRIDGE_CTL_NO_ISA);
+	pci_and_config16(dev, PCI_BRIDGE_CONTROL, ~PCI_BRIDGE_CTL_PARITY);
 
 	/* Enable IO xAPIC on this PCIe port */
 	pci_or_config32(dev, 0xd8, 1 << 7);
diff --git a/src/southbridge/intel/lynxpoint/pcie.c b/src/southbridge/intel/lynxpoint/pcie.c
index 883dfc7..d2950e7 100644
--- a/src/southbridge/intel/lynxpoint/pcie.c
+++ b/src/southbridge/intel/lynxpoint/pcie.c
@@ -667,7 +667,6 @@
 
 	reg16 = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
 	reg16 &= ~PCI_BRIDGE_CTL_PARITY;
-	reg16 |= PCI_BRIDGE_CTL_NO_ISA;
 	pci_write_config16(dev, PCI_BRIDGE_CONTROL, reg16);
 
 	/* Clear errors in status registers */