diff options
Diffstat (limited to 'arch/m68k/mac')
| -rw-r--r-- | arch/m68k/mac/macints.c | 27 | ||||
| -rw-r--r-- | arch/m68k/mac/via.c | 123 |
2 files changed, 108 insertions, 42 deletions
diff --git a/arch/m68k/mac/macints.c b/arch/m68k/mac/macints.c index 41dd164aac2..74f5a97c986 100644 --- a/arch/m68k/mac/macints.c +++ b/arch/m68k/mac/macints.c @@ -151,10 +151,15 @@ irqreturn_t mac_debug_handler(int, void *); /* #define DEBUG_MACINTS */ +static unsigned int mac_irq_startup(struct irq_data *); +static void mac_irq_shutdown(struct irq_data *); + static struct irq_chip mac_irq_chip = { .name = "mac", .irq_enable = mac_irq_enable, .irq_disable = mac_irq_disable, + .irq_startup = mac_irq_startup, + .irq_shutdown = mac_irq_shutdown, }; void __init mac_init_IRQ(void) @@ -274,6 +279,28 @@ void mac_irq_disable(struct irq_data *data) } } +static unsigned int mac_irq_startup(struct irq_data *data) +{ + int irq = data->irq; + + if (IRQ_SRC(irq) == 7 && !oss_present) + via_nubus_irq_startup(irq); + else + mac_irq_enable(data); + + return 0; +} + +static void mac_irq_shutdown(struct irq_data *data) +{ + int irq = data->irq; + + if (IRQ_SRC(irq) == 7 && !oss_present) + via_nubus_irq_shutdown(irq); + else + mac_irq_disable(data); +} + static int num_debug[8]; irqreturn_t mac_debug_handler(int irq, void *dev_id) diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c index 642b44615f7..97996a48b04 100644 --- a/arch/m68k/mac/via.c +++ b/arch/m68k/mac/via.c @@ -63,18 +63,47 @@ static int gIER,gIFR,gBufA,gBufB; #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF) #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8) -/* To disable a NuBus slot on Quadras we make that slot IRQ line an output set - * high. On RBV we just use the slot interrupt enable register. On Macs with - * genuine VIA chips we must use nubus_disabled to keep track of disabled slot - * interrupts. When any slot IRQ is disabled we mask the (edge triggered) CA1 - * or "SLOTS" interrupt. When no slot is disabled, we unmask the CA1 interrupt. - * So, on genuine VIAs, having more than one NuBus IRQ can mean trouble, - * because closing one of those drivers can mask all of the NuBus interrupts. - * Also, since we can't mask the unregistered slot IRQs on genuine VIAs, it's - * possible to get interrupts from cards that MacOS or the ROM has configured - * but we have not. FWIW, "Designing Cards and Drivers for Macintosh II and - * Macintosh SE", page 9-8, says, a slot IRQ with no driver would crash MacOS. + +/* + * On Macs with a genuine VIA chip there is no way to mask an individual slot + * interrupt. This limitation also seems to apply to VIA clone logic cores in + * Quadra-like ASICs. (RBV and OSS machines don't have this limitation.) + * + * We used to fake it by configuring the relevent VIA pin as an output + * (to mask the interrupt) or input (to unmask). That scheme did not work on + * (at least) the Quadra 700. A NuBus card's /NMRQ signal is an open-collector + * circuit (see Designing Cards and Drivers for Macintosh II and Macintosh SE, + * p. 10-11 etc) but VIA outputs are not (see datasheet). + * + * Driving these outputs high must cause the VIA to source current and the + * card to sink current when it asserts /NMRQ. Current will flow but the pin + * voltage is uncertain and so the /NMRQ condition may still cause a transition + * at the VIA2 CA1 input (which explains the lost interrupts). A side effect + * is that a disabled slot IRQ can never be tested as pending or not. + * + * Driving these outputs low doesn't work either. All the slot /NMRQ lines are + * (active low) OR'd together to generate the CA1 (aka "SLOTS") interrupt (see + * The Guide To Macintosh Family Hardware, 2nd edition p. 167). If we drive a + * disabled /NMRQ line low, the falling edge immediately triggers a CA1 + * interrupt and all slot interrupts after that will generate no transition + * and therefore no interrupt, even after being re-enabled. + * + * So we make the VIA port A I/O lines inputs and use nubus_disabled to keep + * track of their states. When any slot IRQ becomes disabled we mask the CA1 + * umbrella interrupt. Only when all slot IRQs become enabled do we unmask + * the CA1 interrupt. It must remain enabled even when cards have no interrupt + * handler registered. Drivers must therefore disable a slot interrupt at the + * device before they call free_irq (like shared and autovector interrupts). + * + * There is also a related problem when MacOS is used to boot Linux. A network + * card brought up by a MacOS driver may raise an interrupt while Linux boots. + * This can be fatal since it can't be handled until the right driver loads + * (if such a driver exists at all). Apparently related to this hardware + * limitation, "Designing Cards and Drivers", p. 9-8, says that a slot + * interrupt with no driver would crash MacOS (the book was written before + * the appearance of Macs with RBV or OSS). */ + static u8 nubus_disabled; void via_debug_dump(void); @@ -354,34 +383,55 @@ void __init via_nubus_init(void) via2[gBufB] |= 0x02; } - /* Disable all the slot interrupts (where possible). */ + /* + * Disable the slot interrupts. On some hardware that's not possible. + * On some hardware it's unclear what all of these I/O lines do. + */ switch (macintosh_config->via_type) { case MAC_VIA_II: - /* Just make the port A lines inputs. */ - switch(macintosh_config->ident) { - case MAC_MODEL_II: - case MAC_MODEL_IIX: - case MAC_MODEL_IICX: - case MAC_MODEL_SE30: - /* The top two bits are RAM size outputs. */ - via2[vDirA] &= 0xC0; - break; - default: - via2[vDirA] &= 0x80; - } + case MAC_VIA_QUADRA: + pr_debug("VIA2 vDirA is 0x%02X\n", via2[vDirA]); break; case MAC_VIA_IIci: /* RBV. Disable all the slot interrupts. SIER works like IER. */ via2[rSIER] = 0x7F; break; + } +} + +void via_nubus_irq_startup(int irq) +{ + int irq_idx = IRQ_IDX(irq); + + switch (macintosh_config->via_type) { + case MAC_VIA_II: case MAC_VIA_QUADRA: - /* Disable the inactive slot interrupts by making those lines outputs. */ - if ((macintosh_config->adb_type != MAC_ADB_PB1) && - (macintosh_config->adb_type != MAC_ADB_PB2)) { - via2[vBufA] |= 0x7F; - via2[vDirA] |= 0x7F; + /* Make the port A line an input. Probably redundant. */ + if (macintosh_config->via_type == MAC_VIA_II) { + /* The top two bits are RAM size outputs. */ + via2[vDirA] &= 0xC0 | ~(1 << irq_idx); + } else { + /* Allow NuBus slots 9 through F. */ + via2[vDirA] &= 0x80 | ~(1 << irq_idx); } + /* fall through */ + case MAC_VIA_IIci: + via_irq_enable(irq); + break; + } +} + +void via_nubus_irq_shutdown(int irq) +{ + switch (macintosh_config->via_type) { + case MAC_VIA_II: + case MAC_VIA_QUADRA: + /* Ensure that the umbrella CA1 interrupt remains enabled. */ + via_irq_enable(irq); + break; + case MAC_VIA_IIci: + via_irq_disable(irq); break; } } @@ -507,6 +557,7 @@ void via_irq_enable(int irq) { } else if (irq_src == 7) { switch (macintosh_config->via_type) { case MAC_VIA_II: + case MAC_VIA_QUADRA: nubus_disabled &= ~(1 << irq_idx); /* Enable the CA1 interrupt when no slot is disabled. */ if (!nubus_disabled) @@ -518,14 +569,6 @@ void via_irq_enable(int irq) { */ via2[rSIER] = IER_SET_BIT(irq_idx); break; - case MAC_VIA_QUADRA: - /* Make the port A line an input to enable the slot irq. - * But not on PowerBooks, that's ADB. - */ - if ((macintosh_config->adb_type != MAC_ADB_PB1) && - (macintosh_config->adb_type != MAC_ADB_PB2)) - via2[vDirA] &= ~(1 << irq_idx); - break; } } } @@ -545,6 +588,7 @@ void via_irq_disable(int irq) { } else if (irq_src == 7) { switch (macintosh_config->via_type) { case MAC_VIA_II: + case MAC_VIA_QUADRA: nubus_disabled |= 1 << irq_idx; if (nubus_disabled) via2[gIER] = IER_CLR_BIT(1); @@ -552,11 +596,6 @@ void via_irq_disable(int irq) { case MAC_VIA_IIci: via2[rSIER] = IER_CLR_BIT(irq_idx); break; - case MAC_VIA_QUADRA: - if ((macintosh_config->adb_type != MAC_ADB_PB1) && - (macintosh_config->adb_type != MAC_ADB_PB2)) - via2[vDirA] |= 1 << irq_idx; - break; } } } |