arch/alpha/kernel/sys_rx164.c

Source file repositories/reference/linux-study-clean/arch/alpha/kernel/sys_rx164.c

File Facts

System
Linux kernel
Corpus path
arch/alpha/kernel/sys_rx164.c
Extension
.c
Size
5180 bytes
Lines
204
Domain
Architecture Layer
Bucket
arch/alpha
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (i == 20) {
			isa_no_iack_sc_device_interrupt(vector);
		} else {
			handle_irq(16+i);
		}
	}
}

static void __init
rx164_init_irq(void)
{
	long i;

	rx164_update_irq_hw(0);
	for (i = 16; i < 40; ++i) {
		irq_set_chip_and_handler(i, &rx164_irq_type, handle_level_irq);
		irq_set_status_flags(i, IRQ_LEVEL);
	}

	init_i8259a_irqs();
	common_init_isa_dma();

	if (request_irq(16 + 20, no_action, 0, "isa-cascade", NULL))
		pr_err("Failed to register isa-cascade interrupt\n");
}


/*
 * The RX164 changed its interrupt routing between pass1 and pass2...
 *
 * PASS1:
 *
 *      Slot    IDSEL   INTA    INTB    INTC    INTD    
 *      0       6       5       10      15      20
 *      1       7       4       9       14      19
 *      2       5       3       8       13      18
 *      3       9       2       7       12      17
 *      4       10      1       6       11      16
 *
 * PASS2:
 *      Slot    IDSEL   INTA    INTB    INTC    INTD    
 *      0       5       1       7       12      17
 *      1       6       2       8       13      18
 *      2       8       3       9       14      19
 *      3       9       4       10      15      20
 *      4       10      5       11      16      6
 *      
 */

/*
 * IdSel       
 *   5  32 bit PCI option slot 0
 *   6  64 bit PCI option slot 1
 *   7  PCI-ISA bridge
 *   7  64 bit PCI option slot 2
 *   9  32 bit PCI option slot 3
 *  10  PCI-PCI bridge
 * 
 */

static int
rx164_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
#if 0
	static char irq_tab_pass1[6][5] __initdata = {
	  /*INT   INTA  INTB  INTC   INTD */
	  { 16+3, 16+3, 16+8, 16+13, 16+18},      /* IdSel 5,  slot 2 */
	  { 16+5, 16+5, 16+10, 16+15, 16+20},     /* IdSel 6,  slot 0 */
	  { 16+4, 16+4, 16+9, 16+14, 16+19},      /* IdSel 7,  slot 1 */
	  { -1,     -1,    -1,    -1,   -1},      /* IdSel 8, PCI/ISA bridge */
	  { 16+2, 16+2, 16+7, 16+12, 16+17},      /* IdSel 9,  slot 3 */
	  { 16+1, 16+1, 16+6, 16+11, 16+16},      /* IdSel 10, slot 4 */
	};
#else
	static char irq_tab[6][5] = {
	  /*INT   INTA  INTB  INTC   INTD */
	  { 16+0, 16+0, 16+6, 16+11, 16+16},      /* IdSel 5,  slot 0 */
	  { 16+1, 16+1, 16+7, 16+12, 16+17},      /* IdSel 6,  slot 1 */
	  { -1,     -1,    -1,    -1,   -1},      /* IdSel 7, PCI/ISA bridge */
	  { 16+2, 16+2, 16+8, 16+13, 16+18},      /* IdSel 8,  slot 2 */
	  { 16+3, 16+3, 16+9, 16+14, 16+19},      /* IdSel 9,  slot 3 */
	  { 16+4, 16+4, 16+10, 16+15, 16+5},      /* IdSel 10, PCI-PCI */
	};
#endif
	const long min_idsel = 5, max_idsel = 10, irqs_per_slot = 5;

	/* JRP - Need to figure out how to distinguish pass1 from pass2,
	   and use the correct table.  */
	return COMMON_TABLE_LOOKUP;
}

Annotation

Implementation Notes