The following commit has been merged into the x86/core branch of tip:
Commit-ID: bc12b70f7d216b36bd87701349374a13e486f8eb
Gitweb: https://git.kernel.org/tip/bc12b70f7d216b36bd87701349374a13e486f8eb
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Thu, 25 Aug 2022 13:36:40 +02:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 29 Aug 2022 12:19:25 +02:00
x86/earlyprintk: Clean up pciserial
While working on a GRUB patch to support PCI-serial, a number of
cleanups were suggested that apply to the code I took inspiration from.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> # pci_ids.h
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/YwdeyCEtW+wa+QhH@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
---
arch/x86/kernel/early_printk.c | 14 +++++++-------
include/linux/pci_ids.h | 3 +++
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c
index 68b3892..44f9370 100644
--- a/arch/x86/kernel/early_printk.c
+++ b/arch/x86/kernel/early_printk.c
@@ -264,11 +264,11 @@ static __init void early_pci_serial_init(char *s)
bar0 = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
/*
- * Verify it is a UART type device
+ * Verify it is a 16550-UART type device
*/
if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) &&
(classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) ||
- (((classcode >> 8) & 0xff) != 0x02)) /* 16550 I/F at BAR0 */ {
+ (((classcode >> 8) & 0xff) != PCI_SERIAL_16550_COMPATIBLE)) {
if (!force)
return;
}
@@ -276,22 +276,22 @@ static __init void early_pci_serial_init(char *s)
/*
* Determine if it is IO or memory mapped
*/
- if (bar0 & 0x01) {
+ if ((bar0 & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
/* it is IO mapped */
serial_in = io_serial_in;
serial_out = io_serial_out;
- early_serial_base = bar0&0xfffffffc;
+ early_serial_base = bar0 & PCI_BASE_ADDRESS_IO_MASK;
write_pci_config(bus, slot, func, PCI_COMMAND,
- cmdreg|PCI_COMMAND_IO);
+ cmdreg|PCI_COMMAND_IO);
} else {
/* It is memory mapped - assume 32-bit alignment */
serial_in = mem32_serial_in;
serial_out = mem32_serial_out;
/* WARNING! assuming the address is always in the first 4G */
early_serial_base =
- (unsigned long)early_ioremap(bar0 & 0xfffffff0, 0x10);
+ (unsigned long)early_ioremap(bar0 & PCI_BASE_ADDRESS_MEM_MASK, 0x10);
write_pci_config(bus, slot, func, PCI_COMMAND,
- cmdreg|PCI_COMMAND_MEMORY);
+ cmdreg|PCI_COMMAND_MEMORY);
}
/*
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index 6feade6..41b3fff 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -75,6 +75,9 @@
#define PCI_CLASS_COMMUNICATION_MODEM 0x0703
#define PCI_CLASS_COMMUNICATION_OTHER 0x0780
+/* Interface for SERIAL/MODEM */
+#define PCI_SERIAL_16550_COMPATIBLE 0x02
+
#define PCI_BASE_CLASS_SYSTEM 0x08
#define PCI_CLASS_SYSTEM_PIC 0x0800
#define PCI_CLASS_SYSTEM_PIC_IOAPIC 0x080010
|