MIPS: Malta: mux & enable SERIRQ interrupt

This patch causes the kernel to mux the SERIRQ interrupt to the SERIRQ
pin of the PIIX4 and to enable that interrupt. The kernel depends upon
the interrupt when using the SuperIO UARTs (ttyS0 & ttyS1) but
previously would not configure it, instead relying upon the bootloader
having done so. If that is not the case then the typical result is that
the system appears to hang once it reaches userland as no output is
displayed on the UART.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6182/
This commit is contained in:
Paul Burton
2013-12-02 16:48:37 +00:00
committed by Ralf Baechle
parent a87ea88d8f
commit ae0d7cbc99
2 changed files with 18 additions and 0 deletions

View File

@@ -54,6 +54,7 @@ int pcibios_plat_dev_init(struct pci_dev *dev)
static void malta_piix_func0_fixup(struct pci_dev *pdev)
{
unsigned char reg_val;
u32 reg_val32;
/* PIIX PIRQC[A:D] irq mappings */
static int piixirqmap[PIIX4_FUNC0_PIRQRC_IRQ_ROUTING_MAX] = {
0, 0, 0, 3,
@@ -83,6 +84,16 @@ static void malta_piix_func0_fixup(struct pci_dev *pdev)
pci_write_config_byte(pdev, PIIX4_FUNC0_TOM, reg_val |
PIIX4_FUNC0_TOM_TOP_OF_MEMORY_MASK);
}
/* Mux SERIRQ to its pin */
pci_read_config_dword(pdev, PIIX4_FUNC0_GENCFG, &reg_val32);
pci_write_config_dword(pdev, PIIX4_FUNC0_GENCFG,
reg_val32 | PIIX4_FUNC0_GENCFG_SERIRQ);
/* Enable SERIRQ */
pci_read_config_byte(pdev, PIIX4_FUNC0_SERIRQC, &reg_val);
reg_val |= PIIX4_FUNC0_SERIRQC_EN | PIIX4_FUNC0_SERIRQC_CONT;
pci_write_config_byte(pdev, PIIX4_FUNC0_SERIRQC, reg_val);
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_0,