diff options
Diffstat (limited to 'arch/powerpc/sysdev/cpm2_pic.c')
| -rw-r--r-- | arch/powerpc/sysdev/cpm2_pic.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/cpm2_pic.c b/arch/powerpc/sysdev/cpm2_pic.c new file mode 100644 index 0000000..5175299 --- /dev/null +++ b/arch/powerpc/sysdev/cpm2_pic.c @@ -0,0 +1,256 @@ +/* + * Platform information definitions. + * + * Copied from arch/ppc/syslib/cpm2_pic.c with minor subsequent updates + * to make in work in arch/powerpc/. Original (c) belongs to Dan Malek. + * + * Author: Vitaly Bordug <vbordug@ru.mvista.com> + * + * 1999-2001 (c) Dan Malek <dan@embeddedalley.com> + * 2006 (c) MontaVista Software, Inc. + * + * 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. + */ + +/* The CPM2 internal interrupt controller. It is usually + * the only interrupt controller. + * There are two 32-bit registers (high/low) for up to 64 + * possible interrupts. + * + * Now, the fun starts.....Interrupt Numbers DO NOT MAP + * in a simple arithmetic fashion to mask or pending registers. + * That is, interrupt 4 does not map to bit position 4. + * We create two tables, indexed by vector number, to indicate + * which register to use and which bit in the register to use. + */ + +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/irq.h> + +#include <asm/immap_cpm2.h> +#include <asm/mpc8260.h> +#include <asm/io.h> +#include <asm/prom.h> + +#include "cpm2_pic.h" + +static struct device_node *cpm2_pic_node; +static struct irq_host *cpm2_pic_host; +#define NR_MASK_WORDS ((NR_IRQS + 31) / 32) +static unsigned long ppc_cached_irq_mask[NR_MASK_WORDS]; + +static const u_char irq_to_siureg[] = { + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0 +}; + +/* bit numbers do not match the docs, these are precomputed so the bit for + * a given irq is (1 << irq_to_siubit[irq]) */ +static const u_char irq_to_siubit[] = { + 0, 15, 14, 13, 12, 11, 10, 9, + 8, 7, 6, 5, 4, 3, 2, 1, + 2, 1, 0, 14, 13, 12, 11, 10, + 9, 8, 7, 6, 5, 4, 3, 0, + 31, 30, 29, 28, 27, 26, 25, 24, + 23, 22, 21, 20, 19, 18, 17, 16, + 16, 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30, 31, +}; + +static void cpm2_mask_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_intctl->ic_simrh); + ppc_cached_irq_mask[word] &= ~(1 << bit); + simr[word] = ppc_cached_irq_mask[word]; +} + +static void cpm2_unmask_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_intctl->ic_simrh); + ppc_cached_irq_mask[word] |= 1 << bit; + simr[word] = ppc_cached_irq_mask[word]; +} + +static void cpm2_mask_and_ack(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr, *sipnr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_intctl->ic_simrh); + sipnr = &(cpm2_intctl->ic_sipnrh); + ppc_cached_irq_mask[word] &= ~(1 << bit); + simr[word] = ppc_cached_irq_mask[word]; + sipnr[word] = 1 << bit; +} + +static void cpm2_end_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS)) + && irq_desc[irq_nr].action) { + + irq_nr -= CPM_IRQ_OFFSET; + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_intctl->ic_simrh); + ppc_cached_irq_mask[word] |= 1 << bit; + simr[word] = ppc_cached_irq_mask[word]; + /* + * Work around large numbers of spurious IRQs on PowerPC 82xx + * systems. + */ + mb(); + } +} + +static struct irq_chip cpm2_pic = { + .typename = " CPM2 SIU ", + .enable = cpm2_unmask_irq, + .disable = cpm2_mask_irq, + .unmask = cpm2_unmask_irq, + .mask_ack = cpm2_mask_and_ack, + .end = cpm2_end_irq, +}; + +int cpm2_get_irq(struct pt_regs *regs) +{ + int irq; + unsigned long bits; + + /* For CPM2, read the SIVEC register and shift the bits down + * to get the irq number. */ + bits = cpm2_intctl->ic_sivec; + irq = bits >> 26; + + if (irq == 0) + return(-1); + return irq+CPM_IRQ_OFFSET; +} + +static int cpm2_pic_host_match(struct irq_host *h, struct device_node *node) +{ + return cpm2_pic_node == NULL || cpm2_pic_node == node; +} + +static int cpm2_pic_host_map(struct irq_host *h, unsigned int virq, + irq_hw_number_t hw) +{ + pr_debug("cpm2_pic_host_map(%d, 0x%lx)\n", virq, hw); + + get_irq_desc(virq)->status |= IRQ_LEVEL; + set_irq_chip_and_handler(virq, &cpm2_pic, handle_level_irq); + return 0; +} + +static void cpm2_host_unmap(struct irq_host *h, unsigned int virq) +{ + /* Make sure irq is masked in hardware */ + cpm2_mask_irq(virq); + + /* remove chip and handler */ + set_irq_chip_and_handler(virq, NULL, NULL); +} + +static int cpm2_pic_host_xlate(struct irq_host *h, struct device_node *ct, + u32 *intspec, unsigned int intsize, + irq_hw_number_t *out_hwirq, unsigned int *out_flags) +{ + static const unsigned char map_cpm2_senses[4] = { + IRQ_TYPE_LEVEL_LOW, + IRQ_TYPE_LEVEL_HIGH, + IRQ_TYPE_EDGE_FALLING, + IRQ_TYPE_EDGE_RISING, + }; + + *out_hwirq = intspec[0]; + if (intsize > 1 && intspec[1] < 4) + *out_flags = map_cpm2_senses[intspec[1]]; + else + *out_flags = IRQ_TYPE_NONE; + + return 0; +} + +static struct irq_host_ops cpm2_pic_host_ops = { + .match = cpm2_pic_host_match, + .map = cpm2_pic_host_map, + .unmap = cpm2_host_unmap, + .xlate = cpm2_pic_host_xlate, +}; + +void cpm2_pic_init(struct device_node *node) +{ + int i; + + /* Clear the CPM IRQ controller, in case it has any bits set + * from the bootloader + */ + + /* Mask out everything */ + + cpm2_intctl->ic_simrh = 0x00000000; + cpm2_intctl->ic_simrl = 0x00000000; + + wmb(); + + /* Ack everything */ + cpm2_intctl->ic_sipnrh = 0xffffffff; + cpm2_intctl->ic_sipnrl = 0xffffffff; + wmb(); + + /* Dummy read of the vector */ + i = cpm2_intctl->ic_sivec; + rmb(); + + /* Initialize the default interrupt mapping priorities, + * in case the boot rom changed something on us. + */ + cpm2_intctl->ic_sicr = 0; + cpm2_intctl->ic_scprrh = 0x05309770; + cpm2_intctl->ic_scprrl = 0x05309770; + + /* create a legacy host */ + if (node) + cpm2_pic_node = of_node_get(node); + + cpm2_pic_host = irq_alloc_host(IRQ_HOST_MAP_LINEAR, 64, &cpm2_pic_host_ops, 64); + if (cpm2_pic_host == NULL) { + printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n"); + return; + } +} |