summaryrefslogtreecommitdiffstats
path: root/arch/arc/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r--arch/arc/kernel/entry-arcv2.S19
-rw-r--r--arch/arc/kernel/intc-arcv2.c41
-rw-r--r--arch/arc/kernel/mcip.c10
-rw-r--r--arch/arc/kernel/setup.c20
-rw-r--r--arch/arc/kernel/time.c8
5 files changed, 64 insertions, 34 deletions
diff --git a/arch/arc/kernel/entry-arcv2.S b/arch/arc/kernel/entry-arcv2.S
index cbfec79..b178302 100644
--- a/arch/arc/kernel/entry-arcv2.S
+++ b/arch/arc/kernel/entry-arcv2.S
@@ -211,7 +211,11 @@ debug_marker_syscall:
; (since IRQ NOT allowed in DS in ARCv2, this can only happen if orig
; entry was via Exception in DS which got preempted in kernel).
;
-; IRQ RTIE won't reliably restore DE bit and/or BTA, needs handling
+; IRQ RTIE won't reliably restore DE bit and/or BTA, needs workaround
+;
+; Solution is return from Intr w/o any delay slot quirks into a kernel trampoline
+; and from pure kernel mode return to delay slot which handles DS bit/BTA correctly
+
.Lintr_ret_to_delay_slot:
debug_marker_ds:
@@ -222,18 +226,23 @@ debug_marker_ds:
ld r2, [sp, PT_ret]
ld r3, [sp, PT_status32]
+ ; STAT32 for Int return created from scratch
+ ; (No delay dlot, disable Further intr in trampoline)
+
bic r0, r3, STATUS_U_MASK|STATUS_DE_MASK|STATUS_IE_MASK|STATUS_L_MASK
st r0, [sp, PT_status32]
mov r1, .Lintr_ret_to_delay_slot_2
st r1, [sp, PT_ret]
+ ; Orig exception PC/STAT32 safekept @orig_r0 and @event stack slots
st r2, [sp, 0]
st r3, [sp, 4]
b .Lisr_ret_fast_path
.Lintr_ret_to_delay_slot_2:
+ ; Trampoline to restore orig exception PC/STAT32/BTA/AUX_USER_SP
sub sp, sp, SZ_PT_REGS
st r9, [sp, -4]
@@ -243,11 +252,19 @@ debug_marker_ds:
ld r9, [sp, 4]
sr r9, [erstatus]
+ ; restore AUX_USER_SP if returning to U mode
+ bbit0 r9, STATUS_U_BIT, 1f
+ ld r9, [sp, PT_sp]
+ sr r9, [AUX_USER_SP]
+
+1:
ld r9, [sp, 8]
sr r9, [erbta]
ld r9, [sp, -4]
add sp, sp, SZ_PT_REGS
+
+ ; return from pure kernel mode to delay slot
rtie
END(ret_from_exception)
diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c
index 0394f9f..9425263 100644
--- a/arch/arc/kernel/intc-arcv2.c
+++ b/arch/arc/kernel/intc-arcv2.c
@@ -14,6 +14,8 @@
#include <linux/irqchip.h>
#include <asm/irq.h>
+static int irq_prio;
+
/*
* Early Hardware specific Interrupt setup
* -Called very early (start_kernel -> setup_arch -> setup_processor)
@@ -24,6 +26,14 @@ void arc_init_IRQ(void)
{
unsigned int tmp;
+ struct irq_build {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ unsigned int pad:3, firq:1, prio:4, exts:8, irqs:8, ver:8;
+#else
+ unsigned int ver:8, irqs:8, exts:8, prio:4, firq:1, pad:3;
+#endif
+ } irq_bcr;
+
struct aux_irq_ctrl {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int res3:18, save_idx_regs:1, res2:1,
@@ -46,28 +56,25 @@ void arc_init_IRQ(void)
WRITE_AUX(AUX_IRQ_CTRL, ictrl);
- /* setup status32, don't enable intr yet as kernel doesn't want */
- tmp = read_aux_reg(0xa);
- tmp |= ISA_INIT_STATUS_BITS;
- tmp &= ~STATUS_IE_MASK;
- asm volatile("flag %0 \n"::"r"(tmp));
-
/*
* ARCv2 core intc provides multiple interrupt priorities (upto 16).
* Typical builds though have only two levels (0-high, 1-low)
* Linux by default uses lower prio 1 for most irqs, reserving 0 for
* NMI style interrupts in future (say perf)
- *
- * Read the intc BCR to confirm that Linux default priority is avail
- * in h/w
- *
- * Note:
- * IRQ_BCR[27..24] contains N-1 (for N priority levels) and prio level
- * is 0 based.
*/
- tmp = (read_aux_reg(ARC_REG_IRQ_BCR) >> 24 ) & 0xF;
- if (ARCV2_IRQ_DEF_PRIO > tmp)
- panic("Linux default irq prio incorrect\n");
+
+ READ_BCR(ARC_REG_IRQ_BCR, irq_bcr);
+
+ irq_prio = irq_bcr.prio; /* Encoded as N-1 for N levels */
+ pr_info("archs-intc\t: %d priority levels (default %d)%s\n",
+ irq_prio + 1, irq_prio,
+ irq_bcr.firq ? " FIRQ (not used)":"");
+
+ /* setup status32, don't enable intr yet as kernel doesn't want */
+ tmp = read_aux_reg(0xa);
+ tmp |= STATUS_AD_MASK | (irq_prio << 1);
+ tmp &= ~STATUS_IE_MASK;
+ asm volatile("flag %0 \n"::"r"(tmp));
}
static void arcv2_irq_mask(struct irq_data *data)
@@ -86,7 +93,7 @@ void arcv2_irq_enable(struct irq_data *data)
{
/* set default priority */
write_aux_reg(AUX_IRQ_SELECT, data->irq);
- write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO);
+ write_aux_reg(AUX_IRQ_PRIORITY, irq_prio);
/*
* hw auto enables (linux unmask) all by default
diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c
index bd237ac..bc771f5 100644
--- a/arch/arc/kernel/mcip.c
+++ b/arch/arc/kernel/mcip.c
@@ -96,13 +96,13 @@ static void mcip_probe_n_setup(void)
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int pad3:8,
idu:1, llm:1, num_cores:6,
- iocoh:1, grtc:1, dbg:1, pad2:1,
+ iocoh:1, gfrc:1, dbg:1, pad2:1,
msg:1, sem:1, ipi:1, pad:1,
ver:8;
#else
unsigned int ver:8,
pad:1, ipi:1, sem:1, msg:1,
- pad2:1, dbg:1, grtc:1, iocoh:1,
+ pad2:1, dbg:1, gfrc:1, iocoh:1,
num_cores:6, llm:1, idu:1,
pad3:8;
#endif
@@ -116,7 +116,7 @@ static void mcip_probe_n_setup(void)
IS_AVAIL1(mp.ipi, "IPI "),
IS_AVAIL1(mp.idu, "IDU "),
IS_AVAIL1(mp.dbg, "DEBUG "),
- IS_AVAIL1(mp.grtc, "GRTC"));
+ IS_AVAIL1(mp.gfrc, "GFRC"));
idu_detected = mp.idu;
@@ -125,8 +125,8 @@ static void mcip_probe_n_setup(void)
__mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xf, 0xf);
}
- if (IS_ENABLED(CONFIG_ARC_HAS_GRTC) && !mp.grtc)
- panic("kernel trying to use non-existent GRTC\n");
+ if (IS_ENABLED(CONFIG_ARC_HAS_GFRC) && !mp.gfrc)
+ panic("kernel trying to use non-existent GFRC\n");
}
struct plat_smp_ops plat_smp_ops = {
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index e1b8744..a7edceb 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -45,6 +45,7 @@ struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
static void read_arc_build_cfg_regs(void)
{
struct bcr_perip uncached_space;
+ struct bcr_timer timer;
struct bcr_generic bcr;
struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
unsigned long perip_space;
@@ -53,7 +54,11 @@ static void read_arc_build_cfg_regs(void)
READ_BCR(AUX_IDENTITY, cpu->core);
READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
- READ_BCR(ARC_REG_TIMERS_BCR, cpu->timers);
+ READ_BCR(ARC_REG_TIMERS_BCR, timer);
+ cpu->extn.timer0 = timer.t0;
+ cpu->extn.timer1 = timer.t1;
+ cpu->extn.rtc = timer.rtc;
+
cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
@@ -208,9 +213,9 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
(unsigned int)(arc_get_core_freq() / 10000) % 100);
n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
- IS_AVAIL1(cpu->timers.t0, "Timer0 "),
- IS_AVAIL1(cpu->timers.t1, "Timer1 "),
- IS_AVAIL2(cpu->timers.rtc, "64-bit RTC ",
+ IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
+ IS_AVAIL1(cpu->extn.timer1, "Timer1 "),
+ IS_AVAIL2(cpu->extn.rtc, "Local-64-bit-Ctr ",
CONFIG_ARC_HAS_RTC));
n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
@@ -293,13 +298,13 @@ static void arc_chk_core_config(void)
struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
int fpu_enabled;
- if (!cpu->timers.t0)
+ if (!cpu->extn.timer0)
panic("Timer0 is not present!\n");
- if (!cpu->timers.t1)
+ if (!cpu->extn.timer1)
panic("Timer1 is not present!\n");
- if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->timers.rtc)
+ if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->extn.rtc)
panic("RTC is not present\n");
#ifdef CONFIG_ARC_HAS_DCCM
@@ -334,6 +339,7 @@ static void arc_chk_core_config(void)
panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
+ IS_ENABLED(CONFIG_ARC_HAS_LLSC) &&
!IS_ENABLED(CONFIG_ARC_STAR_9000923308))
panic("llock/scond livelock workaround missing\n");
}
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index dfad287..156d983 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -62,7 +62,7 @@
/********** Clock Source Device *********/
-#ifdef CONFIG_ARC_HAS_GRTC
+#ifdef CONFIG_ARC_HAS_GFRC
static int arc_counter_setup(void)
{
@@ -83,10 +83,10 @@ static cycle_t arc_counter_read(struct clocksource *cs)
local_irq_save(flags);
- __mcip_cmd(CMD_GRTC_READ_LO, 0);
+ __mcip_cmd(CMD_GFRC_READ_LO, 0);
stamp.l = read_aux_reg(ARC_REG_MCIP_READBACK);
- __mcip_cmd(CMD_GRTC_READ_HI, 0);
+ __mcip_cmd(CMD_GFRC_READ_HI, 0);
stamp.h = read_aux_reg(ARC_REG_MCIP_READBACK);
local_irq_restore(flags);
@@ -95,7 +95,7 @@ static cycle_t arc_counter_read(struct clocksource *cs)
}
static struct clocksource arc_counter = {
- .name = "ARConnect GRTC",
+ .name = "ARConnect GFRC",
.rating = 400,
.read = arc_counter_read,
.mask = CLOCKSOURCE_MASK(64),
OpenPOWER on IntegriCloud