[PATCH V2 17/63] clocksource/drivers/arm_arch_timer: Convert init function to return error

From: Daniel Lezcano
Date: Thu Jun 16 2016 - 17:43:36 EST


The init functions do not return any error. They behave as the following:

- panic, thus leading to a kernel crash while another timer may work and
make the system boot up correctly

or

- print an error and let the caller unaware if the state of the system

Change that by converting the init functions to return an error conforming
to the CLOCKSOURCE_OF_RET prototype.

Proper error handling (rollback, errno value) will be changed later case
by case, thus this change just return back an error or success in the init
function.

Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/clocksource/arm_arch_timer.c | 52 +++++++++++++++++++++++-------------
1 file changed, 33 insertions(+), 19 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 4814446..d0cda68 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -693,25 +693,26 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches)
return needs_probing;
}

-static void __init arch_timer_common_init(void)
+static int __init arch_timer_common_init(void)
{
unsigned mask = ARCH_CP15_TIMER | ARCH_MEM_TIMER;

/* Wait until both nodes are probed if we have two timers */
if ((arch_timers_present & mask) != mask) {
if (arch_timer_needs_probing(ARCH_MEM_TIMER, arch_timer_mem_of_match))
- return;
+ return 0;
if (arch_timer_needs_probing(ARCH_CP15_TIMER, arch_timer_of_match))
- return;
+ return 0;
}

arch_timer_banner(arch_timers_present);
arch_counter_register(arch_timers_present);
- arch_timer_arch_init();
+ return arch_timer_arch_init();
}

-static void __init arch_timer_init(void)
+static int __init arch_timer_init(void)
{
+ int ret;
/*
* If HYP mode is available, we know that the physical timer
* has been configured to be accessible from PL1. Use it, so
@@ -739,23 +740,30 @@ static void __init arch_timer_init(void)

if (!has_ppi) {
pr_warn("arch_timer: No interrupt available, giving up\n");
- return;
+ return -EINVAL;
}
}

- arch_timer_register();
- arch_timer_common_init();
+ ret = arch_timer_register();
+ if (ret)
+ return ret;
+
+ ret = arch_timer_common_init();
+ if (ret)
+ return ret;

arch_timer_kvm_info.virtual_irq = arch_timer_ppi[VIRT_PPI];
+
+ return 0;
}

-static void __init arch_timer_of_init(struct device_node *np)
+static int __init arch_timer_of_init(struct device_node *np)
{
int i;

if (arch_timers_present & ARCH_CP15_TIMER) {
pr_warn("arch_timer: multiple nodes in dt, skipping\n");
- return;
+ return 0;
}

arch_timers_present |= ARCH_CP15_TIMER;
@@ -774,23 +782,23 @@ static void __init arch_timer_of_init(struct device_node *np)
of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
arch_timer_uses_ppi = PHYS_SECURE_PPI;

- arch_timer_init();
+ return arch_timer_init();
}
-CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
-CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);
+CLOCKSOURCE_OF_DECLARE_RET(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init);
+CLOCKSOURCE_OF_DECLARE_RET(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init);

-static void __init arch_timer_mem_init(struct device_node *np)
+static int __init arch_timer_mem_init(struct device_node *np)
{
struct device_node *frame, *best_frame = NULL;
void __iomem *cntctlbase, *base;
- unsigned int irq;
+ unsigned int irq, ret = -EINVAL;
u32 cnttidr;

arch_timers_present |= ARCH_MEM_TIMER;
cntctlbase = of_iomap(np, 0);
if (!cntctlbase) {
pr_err("arch_timer: Can't find CNTCTLBase\n");
- return;
+ return -ENXIO;
}

cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
@@ -830,6 +838,7 @@ static void __init arch_timer_mem_init(struct device_node *np)
best_frame = of_node_get(frame);
}

+ ret= -ENXIO;
base = arch_counter_base = of_iomap(best_frame, 0);
if (!base) {
pr_err("arch_timer: Can't map frame's registers\n");
@@ -841,6 +850,7 @@ static void __init arch_timer_mem_init(struct device_node *np)
else
irq = irq_of_parse_and_map(best_frame, 0);

+ ret = -EINVAL;
if (!irq) {
pr_err("arch_timer: Frame missing %s irq",
arch_timer_mem_use_virtual ? "virt" : "phys");
@@ -848,13 +858,17 @@ static void __init arch_timer_mem_init(struct device_node *np)
}

arch_timer_detect_rate(base, np);
- arch_timer_mem_register(base, irq);
- arch_timer_common_init();
+ ret = arch_timer_mem_register(base, irq);
+ if (ret)
+ goto out;
+
+ return arch_timer_common_init();
out:
iounmap(cntctlbase);
of_node_put(best_frame);
+ return ret;
}
-CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
+CLOCKSOURCE_OF_DECLARE_RET(armv7_arch_timer_mem, "arm,armv7-timer-mem",
arch_timer_mem_init);

#ifdef CONFIG_ACPI
--
1.9.1