build/patch/kernel/archive/mvebu-5.16/10-pcie-bridge-emul.patch

From 4549e5c52af22611dcd847a6b5f9df1ccac57b12 Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Tue, 2 Feb 2021 13:45:28 +0000
Subject: PCI: pci-bridge-emul: re-arrange register tests

Re-arrange the tests for which sets of registers are being accessed
so that it is easier to add further regions later. No functional
change.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/pci/pci-bridge-emul.c | 53 ++++++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 26 deletions(-)

diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c
index db97cddfc85e..49160193840b 100644
--- a/drivers/pci/pci-bridge-emul.c
+++ b/drivers/pci/pci-bridge-emul.c
@@ -328,25 +328,25 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
 	__le32 *cfgspace;
 	const struct pci_bridge_reg_behavior *behavior;
 
-	if (bridge->has_pcie && reg >= PCI_CAP_PCIE_END) {
-		*value = 0;
-		return PCIBIOS_SUCCESSFUL;
-	}
-
-	if (!bridge->has_pcie && reg >= PCI_BRIDGE_CONF_END) {
+	if (reg < PCI_BRIDGE_CONF_END) {
+		/* Emulated PCI space */
+		read_op = bridge->ops->read_base;
+		cfgspace = (__le32 *) &bridge->conf;
+		behavior = bridge->pci_regs_behavior;
+	} else if (!bridge->has_pcie) {
+		/* PCIe space is not implemented, and no PCI capabilities */
 		*value = 0;
 		return PCIBIOS_SUCCESSFUL;
-	}
-
-	if (bridge->has_pcie && reg >= PCI_CAP_PCIE_START) {
+	} else if (reg < PCI_CAP_PCIE_END) {
+		/* Our emulated PCIe capability */
 		reg -= PCI_CAP_PCIE_START;
 		read_op = bridge->ops->read_pcie;
 		cfgspace = (__le32 *) &bridge->pcie_conf;
 		behavior = bridge->pcie_cap_regs_behavior;
 	} else {
-		read_op = bridge->ops->read_base;
-		cfgspace = (__le32 *) &bridge->conf;
-		behavior = bridge->pci_regs_behavior;
+		/* Beyond our PCIe space */
+		*value = 0;
+		return PCIBIOS_SUCCESSFUL;
 	}
 
 	if (read_op)
@@ -390,11 +390,23 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
 	__le32 *cfgspace;
 	const struct pci_bridge_reg_behavior *behavior;
 
-	if (bridge->has_pcie && reg >= PCI_CAP_PCIE_END)
+	if (reg < PCI_BRIDGE_CONF_END) {
+		/* Emulated PCI space */
+		write_op = bridge->ops->write_base;
+		cfgspace = (__le32 *) &bridge->conf;
+		behavior = bridge->pci_regs_behavior;
+	} else if (!bridge->has_pcie) {
+		/* PCIe space is not implemented, and no PCI capabilities */
 		return PCIBIOS_SUCCESSFUL;
-
-	if (!bridge->has_pcie && reg >= PCI_BRIDGE_CONF_END)
+	} else if (reg < PCI_CAP_PCIE_END) {
+		/* Our emulated PCIe capability */
+		reg -= PCI_CAP_PCIE_START;
+		write_op = bridge->ops->write_pcie;
+		cfgspace = (__le32 *) &bridge->pcie_conf;
+		behavior = bridge->pcie_cap_regs_behavior;
+	} else {
 		return PCIBIOS_SUCCESSFUL;
+	}
 
 	shift = (where & 0x3) * 8;
 
@@ -411,17 +423,6 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
 	if (ret != PCIBIOS_SUCCESSFUL)
 		return ret;
 
-	if (bridge->has_pcie && reg >= PCI_CAP_PCIE_START) {
-		reg -= PCI_CAP_PCIE_START;
-		write_op = bridge->ops->write_pcie;
-		cfgspace = (__le32 *) &bridge->pcie_conf;
-		behavior = bridge->pcie_cap_regs_behavior;
-	} else {
-		write_op = bridge->ops->write_base;
-		cfgspace = (__le32 *) &bridge->conf;
-		behavior = bridge->pci_regs_behavior;
-	}
-
 	/* Keep all bits, except the RW bits */
 	new = old & (~mask | ~behavior[reg / 4].rw);
 
-- 
cgit v1.2.3
From 908f7290240209dedf88f91ced8254380ab0c5e5 Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Tue, 2 Feb 2021 13:57:04 +0000
Subject: PCI: pci-bridge-emul: add support for PCIe extended capabilities

Add support for PCIe extended capabilities, which we just redirect to
the emulating driver.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/pci/pci-bridge-emul.c | 74 +++++++++++++++++++++++++++++--------------
 drivers/pci/pci-bridge-emul.h | 15 +++++++++
 2 files changed, 65 insertions(+), 24 deletions(-)

diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c
index 49160193840b..c5e21f1f210b 100644
--- a/drivers/pci/pci-bridge-emul.c
+++ b/drivers/pci/pci-bridge-emul.c
@@ -343,10 +343,16 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
 		read_op = bridge->ops->read_pcie;
 		cfgspace = (__le32 *) &bridge->pcie_conf;
 		behavior = bridge->pcie_cap_regs_behavior;
-	} else {
-		/* Beyond our PCIe space */
+	} else if (reg < PCI_CFG_SPACE_SIZE) {
+		/* Rest of PCI space not implemented */
 		*value = 0;
 		return PCIBIOS_SUCCESSFUL;
+	} else {
+		/* PCIe extended capability space */
+		reg -= PCI_CFG_SPACE_SIZE;
+		read_op = bridge->ops->read_ext;
+		cfgspace = NULL;
+		behavior = NULL;
 	}
 
 	if (read_op)
@@ -354,15 +360,20 @@ int pci_bridge_emul_conf_read(struct pci_bridge_emul *bridge, int where,
 	else
 		ret = PCI_BRIDGE_EMUL_NOT_HANDLED;
 
-	if (ret == PCI_BRIDGE_EMUL_NOT_HANDLED)
-		*value = le32_to_cpu(cfgspace[reg / 4]);
+	if (ret == PCI_BRIDGE_EMUL_NOT_HANDLED) {
+		if (cfgspace)
+			*value = le32_to_cpu(cfgspace[reg / 4]);
+		else
+			*value = 0;
+	}
 
 	/*
 	 * Make sure we never return any reserved bit with a value
 	 * different from 0.
 	 */
-	*value &= behavior[reg / 4].ro | behavior[reg / 4].rw |
-		  behavior[reg / 4].w1c;
+	if (behavior)
+		*value &= behavior[reg / 4].ro | behavior[reg / 4].rw |
+			  behavior[reg / 4].w1c;
 
 	if (size == 1)
 		*value = (*value >> (8 * (where & 3))) & 0xff;
@@ -404,8 +415,15 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
 		write_op = bridge->ops->write_pcie;
 		cfgspace = (__le32 *) &bridge->pcie_conf;
 		behavior = bridge->pcie_cap_regs_behavior;
-	} else {
+	} else if (reg < PCI_CFG_SPACE_SIZE) {
+		/* Rest of PCI space not implemented */
 		return PCIBIOS_SUCCESSFUL;
+	} else {
+		/* PCIe extended capability space */
+		reg -= PCI_CFG_SPACE_SIZE;
+		write_op = bridge->ops->write_ext;
+		cfgspace = NULL;
+		behavior = NULL;
 	}
 
 	shift = (where & 0x3) * 8;
@@ -423,29 +441,37 @@ int pci_bridge_emul_conf_write(struct pci_bridge_emul *bridge, int where,
 	if (ret != PCIBIOS_SUCCESSFUL)
 		return ret;
 
-	/* Keep all bits, except the RW bits */
-	new = old & (~mask | ~behavior[reg / 4].rw);
+	if (behavior) {
+		/* Keep all bits, except the RW bits */
+		new = old & (~mask | ~behavior[reg / 4].rw);
 
-	/* Update the value of the RW bits */
-	new |= (value << shift) & (behavior[reg / 4].rw & mask);
+		/* Update the value of the RW bits */
+		new |= (value << shift) & (behavior[reg / 4].rw & mask);
 
-	/* Clear the W1C bits */
-	new &= ~((value << shift) & (behavior[reg / 4].w1c & mask));
+		/* Clear the W1C bits */
+		new &= ~((value << shift) & (behavior[reg / 4].w1c & mask));
+	} else {
+		new = old & ~mask;
+		new |= (value << shift) & mask;
+	}
 
 	/* Save the new value with the cleared W1C bits into the cfgspace */
-	cfgspace[reg / 4] = cpu_to_le32(new);
+	if (cfgspace)
+		cfgspace[reg / 4] = cpu_to_le32(new);
 
-	/*
-	 * Clear the W1C bits not specified by the write mask, so that the
-	 * write_op() does not clear them.
-	 */
-	new &= ~(behavior[reg / 4].w1c & ~mask);
+	if (behavior) {
+		/*
+		 * Clear the W1C bits not specified by the write mask, so that
+		 * the write_op() does not clear them.
+		 */
+		new &= ~(behavior[reg / 4].w1c & ~mask);
 
-	/*
-	 * Set the W1C bits specified by the write mask, so that write_op()
-	 * knows about that they are to be cleared.
-	 */
-	new |= (value << shift) & (behavior[reg / 4].w1c & mask);
+		/*
+		 * Set the W1C bits specified by the write mask, so that
+		 * write_op() knows about that they are to be cleared.
+		 */
+		new |= (value << shift) & (behavior[reg / 4].w1c & mask);
+	}
 
 	if (write_op)
 		write_op(bridge, reg, old, new, mask);
diff --git a/drivers/pci/pci-bridge-emul.h b/drivers/pci/pci-bridge-emul.h
index 49bbd37ee318..2552ab660b08 100644
--- a/drivers/pci/pci-bridge-emul.h
+++ b/drivers/pci/pci-bridge-emul.h
@@ -90,6 +90,14 @@ struct pci_bridge_emul_ops {
 	 */
 	pci_bridge_emul_read_status_t (*read_pcie)(struct pci_bridge_emul *bridge,
 						   int reg, u32 *value);
+
+	/*
+	 * Same as ->read_base(), except it is for reading from the
+	 * PCIe extended capability configuration space.
+	 */
+	pci_bridge_emul_read_status_t (*read_ext)(struct pci_bridge_emul *bridge,
+						  int reg, u32 *value);
+
 	/*
 	 * Called when writing to the regular PCI bridge configuration
 	 * space. old is the current value, new is the new value being
@@ -105,6 +113,13 @@ struct pci_bridge_emul_ops {
 	 */
 	void (*write_pcie)(struct pci_bridge_emul *bridge, int reg,
 			   u32 old, u32 new, u32 mask);
+
+	/*
+	 * Same as ->write_base(), except it is for writing from the
+	 * PCIe extended capability configuration space.
+	 */
+	void (*write_ext)(struct pci_bridge_emul *bridge, int reg,
+			  u32 old, u32 new, u32 mask);
 };
 
 struct pci_bridge_reg_behavior;
-- 
cgit v1.2.3