diff options
Diffstat (limited to 'arch/powerpc/sysdev/xilinx_intc.c')
-rw-r--r-- | arch/powerpc/sysdev/xilinx_intc.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c new file mode 100644 index 000000000..4a86dcff3 --- /dev/null +++ b/arch/powerpc/sysdev/xilinx_intc.c @@ -0,0 +1,88 @@ +/* + * Interrupt controller driver for Xilinx Virtex FPGAs + * + * Copyright (C) 2007 Secret Lab Technologies Ltd. + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + * + */ + +/* + * This is a driver for the interrupt controller typically found in + * Xilinx Virtex FPGA designs. + * + * The interrupt sense levels are hard coded into the FPGA design with + * typically a 1:1 relationship between irq lines and devices (no shared + * irq lines). Therefore, this driver does not attempt to handle edge + * and level interrupts differently. + */ +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/irq.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <asm/io.h> +#include <asm/processor.h> +#include <asm/i8259.h> +#include <asm/irq.h> +#include <linux/irqchip.h> + +#if defined(CONFIG_PPC_I8259) +/* + * Support code for cascading to 8259 interrupt controllers + */ +static void xilinx_i8259_cascade(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + unsigned int cascade_irq = i8259_irq(); + + if (cascade_irq) + generic_handle_irq(cascade_irq); + + /* Let xilinx_intc end the interrupt */ + chip->irq_unmask(&desc->irq_data); +} + +static void __init xilinx_i8259_setup_cascade(void) +{ + struct device_node *cascade_node; + int cascade_irq; + + /* Initialize i8259 controller */ + cascade_node = of_find_compatible_node(NULL, NULL, "chrp,iic"); + if (!cascade_node) + return; + + cascade_irq = irq_of_parse_and_map(cascade_node, 0); + if (!cascade_irq) { + pr_err("virtex_ml510: Failed to map cascade interrupt\n"); + goto out; + } + + i8259_init(cascade_node, 0); + irq_set_chained_handler(cascade_irq, xilinx_i8259_cascade); + + /* Program irq 7 (usb/audio), 14/15 (ide) to level sensitive */ + /* This looks like a dirty hack to me --gcl */ + outb(0xc0, 0x4d0); + outb(0xc0, 0x4d1); + + out: + of_node_put(cascade_node); +} +#else +static inline void xilinx_i8259_setup_cascade(void) { return; } +#endif /* defined(CONFIG_PPC_I8259) */ + +/* + * Initialize master Xilinx interrupt controller + */ +void __init xilinx_intc_init_tree(void) +{ + irqchip_init(); + xilinx_i8259_setup_cascade(); +} |