From bea12b782337105feeb3aeb0875d110eed007803 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Tue, 26 Nov 2013 17:45:27 +0000 Subject: malta: enable PIIX4 SERIRQ Whilst U-boot does not require this itself, Linux currently relies upon it having been muxed and enabled by the bootloader. Thus in order to preserve compatibility with current kernels before a fix is merged in Linux we will enable the SERIRQ interrupt and mux it to its pin. Without doing this current kernels will never receive serial port interrupts and the end result is typically that userland appears to hang. Signed-off-by: Paul Burton --- board/imgtec/malta/malta.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'board/imgtec') diff --git a/board/imgtec/malta/malta.c b/board/imgtec/malta/malta.c index a1a4c01866..d363e49919 100644 --- a/board/imgtec/malta/malta.c +++ b/board/imgtec/malta/malta.c @@ -171,6 +171,8 @@ struct serial_device *default_serial_console(void) void pci_init_board(void) { pci_dev_t bdf; + u32 val32; + u8 val8; switch (malta_sys_con()) { case SYSCON_GT64120: @@ -205,4 +207,14 @@ void pci_init_board(void) pci_write_config_byte(bdf, PCI_CFG_PIIX4_PIRQRCB, 10); pci_write_config_byte(bdf, PCI_CFG_PIIX4_PIRQRCC, 11); pci_write_config_byte(bdf, PCI_CFG_PIIX4_PIRQRCD, 11); + + /* mux SERIRQ onto SERIRQ pin */ + pci_read_config_dword(bdf, PCI_CFG_PIIX4_GENCFG, &val32); + val32 |= PCI_CFG_PIIX4_GENCFG_SERIRQ; + pci_write_config_dword(bdf, PCI_CFG_PIIX4_GENCFG, val32); + + /* enable SERIRQ - Linux currently depends upon this */ + pci_read_config_byte(bdf, PCI_CFG_PIIX4_SERIRQC, &val8); + val8 |= PCI_CFG_PIIX4_SERIRQC_EN | PCI_CFG_PIIX4_SERIRQC_CONT; + pci_write_config_byte(bdf, PCI_CFG_PIIX4_SERIRQC, val8); } -- cgit v1.2.1