From f16f7fc491c933a17bcc06b86fc5f2b0a6fa59d5 Mon Sep 17 00:00:00 2001
From: "Charles E. Youse" <charles.youse@intel.com>
Date: Wed, 1 May 2019 11:21:32 -0700
Subject: [PATCH] drivers/pcie: add support to read wired IRQ configuration

Firmware is supposed to set a register in PCI configuration space which
indicates the hardware IRQ that the endpoint is attached to.

A function is implemented which reads this register, and the PCIe shell
is updated to use it instead of doing it "manually".

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
---
 drivers/pcie/pcie.c         | 7 +++++++
 drivers/pcie/shell.c        | 8 ++++----
 include/drivers/pcie/pcie.h | 8 ++++++++
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/pcie/pcie.c b/drivers/pcie/pcie.c
index 80f4d9bea2e..b79b9e6272e 100644
--- a/drivers/pcie/pcie.c
+++ b/drivers/pcie/pcie.c
@@ -79,6 +79,13 @@ u32_t pcie_get_mbar(pcie_bdf_t bdf, unsigned int index)
 	return pcie_get_bar(bdf, index, false);
 }
 
+unsigned int pcie_wired_irq(pcie_bdf_t bdf)
+{
+	u32_t data = pcie_conf_read(bdf, PCIE_CONF_INTR);
+
+	return PCIE_CONF_INTR_IRQ(data);
+}
+
 u32_t pcie_get_iobar(pcie_bdf_t bdf, unsigned int index)
 {
 	return pcie_get_bar(bdf, index, true);
diff --git a/drivers/pcie/shell.c b/drivers/pcie/shell.c
index c0adba9d903..0da9aea4da8 100644
--- a/drivers/pcie/shell.c
+++ b/drivers/pcie/shell.c
@@ -58,6 +58,7 @@ static void show_bars(const struct shell *shell, pcie_bdf_t bdf)
 static void show(const struct shell *shell, pcie_bdf_t bdf)
 {
 	u32_t data;
+	unsigned int irq;
 
 	data = pcie_conf_read(bdf, PCIE_CONF_ID);
 
@@ -88,11 +89,10 @@ static void show(const struct shell *shell, pcie_bdf_t bdf)
 		shell_fprintf(shell, SHELL_NORMAL, "\n");
 		show_bars(shell, bdf);
 		show_msi(shell, bdf);
-		data = pcie_conf_read(bdf, PCIE_CONF_INTR);
-		if (PCIE_CONF_INTR_IRQ(data) != PCIE_CONF_INTR_IRQ_NONE) {
+		irq = pcie_wired_irq(bdf);
+		if (irq != PCIE_CONF_INTR_IRQ_NONE) {
 			shell_fprintf(shell, SHELL_NORMAL,
-				      "    wired interrupt on IRQ %d\n",
-				      PCIE_CONF_INTR_IRQ(data));
+				      "    wired interrupt on IRQ %d\n", irq);
 		}
 	}
 }
diff --git a/include/drivers/pcie/pcie.h b/include/drivers/pcie/pcie.h
index 16dfe71c1db..7811e6b26b6 100644
--- a/include/drivers/pcie/pcie.h
+++ b/include/drivers/pcie/pcie.h
@@ -103,6 +103,14 @@ extern u32_t pcie_get_iobar(pcie_bdf_t bdf, unsigned int index);
  */
 extern void pcie_set_cmd(pcie_bdf_t bdf, u32_t bits, bool on);
 
+/**
+ * @brief Return the IRQ assigned by the firmware/board to an endpoint.
+ *
+ * @param bdf the PCI(e) endpoint
+ * @return the IRQ number, or PCIE_CONF_INTR_IRQ_NONE if unknown.
+ */
+extern unsigned int pcie_wired_irq(pcie_bdf_t bdf);
+
 /**
  * @brief Enable the PCI(e) endpoint to generate the specified IRQ.
  *