Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c
index acdabbe..3c2cfcb 100644
--- a/arch/m68k/mac/via.c
+++ b/arch/m68k/mac/via.c
@@ -23,6 +23,7 @@
*
*/
+#include <linux/clocksource.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
@@ -55,16 +56,6 @@
static int gIER,gIFR,gBufA,gBufB;
/*
- * Timer defs.
- */
-
-#define TICK_SIZE 10000
-#define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */
-#define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF)
-#define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8)
-
-
-/*
* 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.)
@@ -189,7 +180,6 @@
/*
* SE/30: disable video IRQ
- * XXX: testing for SE/30 VBL
*/
if (macintosh_config->ident == MAC_MODEL_SE30) {
@@ -197,13 +187,18 @@
via1[vBufB] |= 0x40;
}
- /*
- * Set the RTC bits to a known state: all lines to outputs and
- * RTC disabled (yes that's 0 to enable and 1 to disable).
- */
-
- via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
- via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
+ switch (macintosh_config->adb_type) {
+ case MAC_ADB_IOP:
+ case MAC_ADB_II:
+ case MAC_ADB_PB1:
+ /*
+ * Set the RTC bits to a known state: all lines to outputs and
+ * RTC disabled (yes that's 0 to enable and 1 to disable).
+ */
+ via1[vDirB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData;
+ via1[vBufB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk;
+ break;
+ }
/* Everything below this point is VIA2/RBV only... */
@@ -268,22 +263,6 @@
}
/*
- * Start the 100 Hz clock
- */
-
-void __init via_init_clock(irq_handler_t func)
-{
- via1[vACR] |= 0x40;
- via1[vT1LL] = MAC_CLOCK_LOW;
- via1[vT1LH] = MAC_CLOCK_HIGH;
- via1[vT1CL] = MAC_CLOCK_LOW;
- via1[vT1CH] = MAC_CLOCK_HIGH;
-
- if (request_irq(IRQ_MAC_TIMER_1, func, 0, "timer", func))
- pr_err("Couldn't register %s interrupt\n", "timer");
-}
-
-/*
* Debugging dump, used in various places to see what's going on.
*/
@@ -311,29 +290,6 @@
}
/*
- * This is always executed with interrupts disabled.
- *
- * TBI: get time offset between scheduling timer ticks
- */
-
-u32 mac_gettimeoffset(void)
-{
- unsigned long ticks, offset = 0;
-
- /* read VIA1 timer 2 current value */
- ticks = via1[vT1CL] | (via1[vT1CH] << 8);
- /* The probability of underflow is less than 2% */
- if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
- /* Check for pending timer interrupt in VIA1 IFR */
- if (via1[vIFR] & 0x40) offset = TICK_SIZE;
-
- ticks = MAC_CLOCK_TICK - ticks;
- ticks = ticks * 10000L / MAC_CLOCK_TICK;
-
- return (ticks + offset) * 1000;
-}
-
-/*
* Flush the L2 cache on Macs that have it by flipping
* the system into 24-bit mode for an instant.
*/
@@ -436,6 +392,8 @@
* via6522.c :-), disable/pending masks added.
*/
+#define VIA_TIMER_1_INT BIT(6)
+
void via1_irq(struct irq_desc *desc)
{
int irq_num;
@@ -445,6 +403,21 @@
if (!events)
return;
+ irq_num = IRQ_MAC_TIMER_1;
+ irq_bit = VIA_TIMER_1_INT;
+ if (events & irq_bit) {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ via1[vIFR] = irq_bit;
+ generic_handle_irq(irq_num);
+ local_irq_restore(flags);
+
+ events &= ~irq_bit;
+ if (!events)
+ return;
+ }
+
irq_num = VIA1_SOURCE_BASE;
irq_bit = 1;
do {
@@ -601,3 +574,82 @@
return via2[gIFR] & (1 << IRQ_IDX(IRQ_MAC_SCSIDRQ));
}
EXPORT_SYMBOL(via2_scsi_drq_pending);
+
+/* timer and clock source */
+
+#define VIA_CLOCK_FREQ 783360 /* VIA "phase 2" clock in Hz */
+#define VIA_TIMER_CYCLES (VIA_CLOCK_FREQ / HZ) /* clock cycles per jiffy */
+
+#define VIA_TC (VIA_TIMER_CYCLES - 2) /* including 0 and -1 */
+#define VIA_TC_LOW (VIA_TC & 0xFF)
+#define VIA_TC_HIGH (VIA_TC >> 8)
+
+static u64 mac_read_clk(struct clocksource *cs);
+
+static struct clocksource mac_clk = {
+ .name = "via1",
+ .rating = 250,
+ .read = mac_read_clk,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static u32 clk_total, clk_offset;
+
+static irqreturn_t via_timer_handler(int irq, void *dev_id)
+{
+ irq_handler_t timer_routine = dev_id;
+
+ clk_total += VIA_TIMER_CYCLES;
+ clk_offset = 0;
+ timer_routine(0, NULL);
+
+ return IRQ_HANDLED;
+}
+
+void __init via_init_clock(irq_handler_t timer_routine)
+{
+ if (request_irq(IRQ_MAC_TIMER_1, via_timer_handler, IRQF_TIMER, "timer",
+ timer_routine)) {
+ pr_err("Couldn't register %s interrupt\n", "timer");
+ return;
+ }
+
+ via1[vT1LL] = VIA_TC_LOW;
+ via1[vT1LH] = VIA_TC_HIGH;
+ via1[vT1CL] = VIA_TC_LOW;
+ via1[vT1CH] = VIA_TC_HIGH;
+ via1[vACR] |= 0x40;
+
+ clocksource_register_hz(&mac_clk, VIA_CLOCK_FREQ);
+}
+
+static u64 mac_read_clk(struct clocksource *cs)
+{
+ unsigned long flags;
+ u8 count_high;
+ u16 count;
+ u32 ticks;
+
+ /*
+ * Timer counter wrap-around is detected with the timer interrupt flag
+ * but reading the counter low byte (vT1CL) would reset the flag.
+ * Also, accessing both counter registers is essentially a data race.
+ * These problems are avoided by ignoring the low byte. Clock accuracy
+ * is 256 times worse (error can reach 0.327 ms) but CPU overhead is
+ * reduced by avoiding slow VIA register accesses.
+ */
+
+ local_irq_save(flags);
+ count_high = via1[vT1CH];
+ if (count_high == 0xFF)
+ count_high = 0;
+ if (count_high > 0 && (via1[vIFR] & VIA_TIMER_1_INT))
+ clk_offset = VIA_TIMER_CYCLES;
+ count = count_high << 8;
+ ticks = VIA_TIMER_CYCLES - count;
+ ticks += clk_offset + clk_total;
+ local_irq_restore(flags);
+
+ return ticks;
+}