[U-Boot] [PATCH 11/13] x86: irq: Introduce CONFIG_DISCRETE_PIRQ_ROUT

[Bin Meng]

Currently both pirq_reg_to_linkno() and pirq_linkno_to_reg() assume
consecutive PIRQ routing control registers. But this is not always
the case on some platforms. Introduce a Kconfig option for this and
adjust the irq router driver to be able to use platform-specific
converting logic.

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

 arch/x86/Kconfig           | 9 +++++++++
 arch/x86/cpu/irq.c         | 3 +++
 arch/x86/include/asm/irq.h | 2 ++
 3 files changed, 14 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5c23b2c..c145799 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -686,6 +686,15 @@ config STACK_SIZE
 	  Estimated U-Boot's runtime stack size that needs to be reserved
 	  during an ACPI S3 resume.
 
+config DISCRETE_PIRQ_ROUT
+	bool
+	help
+	  This variable indicates that the chipset's PIRQ routing control
+	  registers are not consecutive. If this is the case, the platform
+	  codes must provide two inline functions for the IRQ router driver
+	  to convert PIRQ routing control register offset to link number.
+	  See pirq_reg_to_linkno() and pirq_linkno_to_reg().
+
 config MAX_PIRQ_LINKS
 	int
 	default 8
diff --git a/arch/x86/cpu/irq.c b/arch/x86/cpu/irq.c
index ec556d3..e33be61 100644
--- a/arch/x86/cpu/irq.c
+++ b/arch/x86/cpu/irq.c
@@ -13,6 +13,9 @@
 #include <asm/pci.h>
 #include <asm/pirq_routing.h>
 #include <asm/tables.h>
+#ifdef CONFIG_DISCRETE_PIRQ_ROUT
+#include <asm/arch/irq.h>
+#endif
 
 DECLARE_GLOBAL_DATA_PTR;
 
diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index bfa58cf..468a29f 100644
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -52,6 +52,7 @@ struct pirq_routing {
 	int pirq;
 };
 
+#ifndef CONFIG_DISCRETE_PIRQ_ROUT
 /**
  * pirq_reg_to_linkno() - Convert a PIRQ routing register offset to link number
  *
@@ -75,6 +76,7 @@ static inline int pirq_linkno_to_reg(int linkno, int base)
 {
 	return linkno + base;
 }
+#endif
 
 #define PIRQ_BITMAP		0xdef8
 
-- 
2.7.4