patch-2.3.17 linux/arch/m68k/mac/psc.c

• Lines: 204
• Date: Sat Sep 4 13:06:41 1999
• Orig file: v2.3.16/linux/arch/m68k/mac/psc.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.16/linux/arch/m68k/mac/psc.c linux/arch/m68k/mac/psc.c
@@ -0,0 +1,203 @@
+/*
+ *	Apple Peripheral System Controller (PSC)
+ *
+ *	The PSC is used on the AV Macs to control IO functions not handled
+ *	by the VIAs (Ethernet, DSP, SCC).
+ *
+ * TO DO:
+ *
+ * Try to figure out what's going on in pIFR5 and pIFR6. There seem to be
+ * persisant interrupt conditions in those registers and I have no idea what
+ * they are. Granted it doesn't affect since we're not enabling any interrupts
+ * on those levels at the moment, but it would be nice to know. I have a feeling
+ * they aren't actually interrupt lines but data lines (to the DSP?)
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+
+#include <asm/traps.h>
+#include <asm/bootinfo.h> 
+#include <asm/macintosh.h> 
+#include <asm/macints.h> 
+#include <asm/mac_psc.h>
+
+#define DEBUG_PSC
+
+int psc_present;
+volatile __u8 *psc;
+
+void psc_irq(int, void *, struct pt_regs *);
+
+extern int console_loglevel;
+
+/*
+ * Debugging dump, used in various places to see what's going on.
+ */
+
+void psc_debug_dump(void)
+{
+	int	i;
+
+	if (!psc_present) return;
+	for (i = 0x30 ; i < 0x70 ; i += 0x10) {
+		printk("PSC #%d:  IFR = 0x%02X IER = 0x%02X\n",
+			i >> 4,
+			(int) psc_read_byte(pIFRbase + i),
+			(int) psc_read_byte(pIERbase + i));
+	}
+}
+
+/*
+ * Try to kill all DMA channels on the PSC. Not sure how this his
+ * supposed to work; this is code lifted from macmace.c and then
+ * expanded to cover what I think are the other 7 channels.
+ */
+
+void psc_dma_die_die_die(void)
+{
+	int i;
+
+	printk("Killing all PSC DMA channels...");
+	for (i = 0 ; i < 9 ; i++) {
+		psc_write_word(PSC_CTL_BASE + (i << 4), 0x8800);
+		psc_write_word(PSC_CTL_BASE + (i << 4), 0x1000);
+		psc_write_word(PSC_CMD_BASE + (i << 5), 0x1100);
+		psc_write_word(PSC_CMD_BASE + (i << 5) + 0x10, 0x1100);
+	}
+	printk("done!\n");
+}
+
+/*
+ * Initialize the PSC. For now this just involves shutting down all
+ * interrupt sources using the IERs.
+ */
+
+void __init psc_init(void)
+{
+	int i;
+
+	if (macintosh_config->ident != MAC_MODEL_C660
+	 && macintosh_config->ident != MAC_MODEL_Q840)
+	{
+		psc = NULL;
+		psc_present = 0;
+		return;
+	}
+
+	/*
+	 * The PSC is always at the same spot, but using psc
+	 * keeps things consisant with the psc_xxxx functions.
+	 */
+
+	psc = (void *) PSC_BASE;
+	psc_present = 1;
+
+	printk("PSC detected at %p\n", psc);
+
+	psc_dma_die_die_die();
+
+#ifdef DEBUG_PSC
+	psc_debug_dump();
+#endif
+	/*
+	 * Mask and clear all possible interrupts
+	 */
+
+	for (i = 0x30 ; i < 0x70 ; i += 0x10) {
+		psc_write_byte(pIERbase + i, 0x0F);
+		psc_write_byte(pIFRbase + i, 0x0F);
+	}
+}
+
+/*
+ * Register the PSC interrupt dispatchers for autovector interrupts 3-6.
+ */
+
+void __init psc_register_interrupts(void)
+{
+	request_irq(3, psc_irq, IRQ_FLG_LOCK, "PSC Dispatch",
+		    (void *) 0x30);
+	request_irq(4, psc_irq, IRQ_FLG_LOCK, "PSC Dispatch",
+		    (void *) 0x40);
+	request_irq(5, psc_irq, IRQ_FLG_LOCK, "PSC Dispatch",
+		    (void *) 0x50);
+	request_irq(6, psc_irq, IRQ_FLG_LOCK, "PSC Dispatch",
+		    (void *) 0x60);
+}
+
+/*
+ * PSC interrupt handler. It's a lot like the VIA interrupt handler.
+ */
+
+void psc_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+	int pIFR	= pIFRbase + ((int) dev_id);
+	int pIER	= pIERbase + ((int) dev_id);
+	int base_irq;
+	int irq_bit,i;
+	unsigned char events;
+
+	irq -= VEC_SPUR;
+	base_irq = irq << 3;
+
+#ifdef DEBUG_IRQS
+	printk("psc_irq: irq %d pIFR = 0x%02X pIER = 0x%02X\n",
+		irq, (int) psc_read_byte(pIFR), (int) psc_read_byte(pIER));
+#endif
+
+	events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF;
+	if (!events) return;
+
+	for (i = 0, irq_bit = 1 ; i < 4 ; i++, irq_bit <<= 1) {
+	        if (events & irq_bit) {
+			psc_write_byte(pIER, irq_bit);
+			mac_do_irq_list(base_irq + i, regs);
+			psc_write_byte(pIFR, irq_bit);
+			psc_write_byte(pIER, irq_bit | 0x80);
+		}
+	}
+}
+
+void psc_irq_enable(int irq) {
+	int irq_src	= IRQ_SRC(irq);
+	int irq_idx	= IRQ_IDX(irq);
+	int pIER	= pIERbase + (irq_src << 4);
+
+#ifdef DEBUG_IRQUSE
+	printk("psc_irq_enable(%d)\n", irq);
+#endif
+	psc_write_byte(pIER, (1 << irq_idx) | 0x80);
+}
+
+void psc_irq_disable(int irq) {
+	int irq_src	= IRQ_SRC(irq);
+	int irq_idx	= IRQ_IDX(irq);
+	int pIER	= pIERbase + (irq_src << 4);
+
+#ifdef DEBUG_IRQUSE
+	printk("psc_irq_disable(%d)\n", irq);
+#endif
+	psc_write_byte(pIER, 1 << irq_idx);
+}
+
+void psc_irq_clear(int irq) {
+	int irq_src	= IRQ_SRC(irq);
+	int irq_idx	= IRQ_IDX(irq);
+	int pIFR	= pIERbase + (irq_src << 4);
+
+	psc_write_byte(pIFR, 1 << irq_idx);
+}
+
+int psc_irq_pending(int irq)
+{
+	int irq_src	= IRQ_SRC(irq);
+	int irq_idx	= IRQ_IDX(irq);
+	int pIFR	= pIERbase + (irq_src << 4);
+
+	return psc_read_byte(pIFR) & (1 << irq_idx);
+}