x86/msi: Provide msi message shadow structs

Create shadow structs with named bitfields for msi_msg data, address_lo and
address_hi and use them in the MSI message composer.

Provide a function to retrieve the destination ID. This could be inline,
but that'd create a circular header dependency.

[dwmw2: fix bitfields not all to be a union]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-13-dwmw2@infradead.org

1 files changed, 49 insertions, 0 deletions

diff --git a/arch/x86/include/asm/msi.h b/arch/x86/include/asm/msi.h
index cd30013d15d3..322fd905da9c 100644
--- a/arch/x86/include/asm/msi.h
+++ b/arch/x86/include/asm/msi.h
@@ -9,4 +9,53 @@ typedef struct irq_alloc_info msi_alloc_info_t;
 int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
 		    msi_alloc_info_t *arg);
 
+/* Structs and defines for the X86 specific MSI message format */
+
+typedef struct x86_msi_data {
+	u32	vector			:  8,
+		delivery_mode		:  3,
+		dest_mode_logical	:  1,
+		reserved		:  2,
+		active_low		:  1,
+		is_level		:  1;
+
+	u32	dmar_subhandle;
+} __attribute__ ((packed)) arch_msi_msg_data_t;
+#define arch_msi_msg_data	x86_msi_data
+
+typedef struct x86_msi_addr_lo {
+	union {
+		struct {
+			u32	reserved_0		:  2,
+				dest_mode_logical	:  1,
+				redirect_hint		:  1,
+				reserved_1		:  8,
+				destid_0_7		:  8,
+				base_address		: 12;
+		};
+		struct {
+			u32	dmar_reserved_0		:  2,
+				dmar_index_15		:  1,
+				dmar_subhandle_valid	:  1,
+				dmar_format		:  1,
+				dmar_index_0_14		: 15,
+				dmar_base_address	: 12;
+		};
+	};
+} __attribute__ ((packed)) arch_msi_msg_addr_lo_t;
+#define arch_msi_msg_addr_lo	x86_msi_addr_lo
+
+#define X86_MSI_BASE_ADDRESS_LOW	(0xfee00000 >> 20)
+
+typedef struct x86_msi_addr_hi {
+	u32	reserved		:  8,
+		destid_8_31		: 24;
+} __attribute__ ((packed)) arch_msi_msg_addr_hi_t;
+#define arch_msi_msg_addr_hi	x86_msi_addr_hi
+
+#define X86_MSI_BASE_ADDRESS_HIGH	(0)
+
+struct msi_msg;
+u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid);
+
 #endif /* _ASM_X86_MSI_H */