[PATCH] staging: comedi: ni_tio: Allocate shadow regs for each counter chip
Ian Abbott
abbotti at mev.co.uk
Mon Feb 25 15:06:11 UTC 2019
The "ni_tio" module contains code to allocate, destroy and operate on a
`struct ni_gpct_device`, which represents a number of counters spread
over one or more blocks (or "chips"). `struct ni_gpct_device` includes
an array member `regs` holding shadow copies of register values.
Unfortunately, this is currently shared by each block of counters so
they interfere with each other. This is a problem for the "ni_660x"
module, which has 8 counters spread over 2 blocks. The `regs` storage
needs to be two-dimensional, indexed by block (chip) number and register
number. (It does not need to be three-dimensional because the registers
for individual counters are intermingled within the block.)
Change the `regs` member to an array pointer that can be indexed like a
two-dimensional array to access the shadow storage for each register in
each block. Allocate the storage in `ni_gpct_device_construct()` and
free it in `ni_gpct_device_destroy()`. (`ni_gpct_device_construct()`
can determine the number of blocks from the `num_counters` and
`counters_per_chip` parameters.)
Add new member `num_chips` to hold the number of chips. Use that to
check that `chip_index` value is in range in the same places that
check the register offset is in range.
Remove the `counters_per_chip` member of `struct ni_gpct_device` as it
is not needed anywhere and could be easily derived from the
`num_counters` and `num_chips` members if required.
Thanks to GitHub user "raabej" (real name unknown) for an initial
implementation of this in the out-of-tree fork of the Comedi drivers.
Signed-off-by: Ian Abbott <abbotti at mev.co.uk>
---
drivers/staging/comedi/drivers/ni_tio.c | 71 ++++++++++++++++---------
drivers/staging/comedi/drivers/ni_tio.h | 4 +-
2 files changed, 47 insertions(+), 28 deletions(-)
diff --git a/drivers/staging/comedi/drivers/ni_tio.c b/drivers/staging/comedi/drivers/ni_tio.c
index 0eb388c0e1f0..048cb35723ad 100644
--- a/drivers/staging/comedi/drivers/ni_tio.c
+++ b/drivers/staging/comedi/drivers/ni_tio.c
@@ -224,13 +224,16 @@ static void ni_tio_set_bits_transient(struct ni_gpct *counter,
unsigned int transient)
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
+ unsigned int chip = counter->chip_index;
unsigned long flags;
- if (reg < NITIO_NUM_REGS) {
+ if (reg < NITIO_NUM_REGS && chip < counter_dev->num_chips) {
+ unsigned int *regs = counter_dev->regs[chip];
+
spin_lock_irqsave(&counter_dev->regs_lock, flags);
- counter_dev->regs[reg] &= ~mask;
- counter_dev->regs[reg] |= (value & mask);
- ni_tio_write(counter, counter_dev->regs[reg] | transient, reg);
+ regs[reg] &= ~mask;
+ regs[reg] |= (value & mask);
+ ni_tio_write(counter, regs[reg] | transient, reg);
mmiowb();
spin_unlock_irqrestore(&counter_dev->regs_lock, flags);
}
@@ -267,12 +270,13 @@ unsigned int ni_tio_get_soft_copy(const struct ni_gpct *counter,
enum ni_gpct_register reg)
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
+ unsigned int chip = counter->chip_index;
unsigned int value = 0;
unsigned long flags;
- if (reg < NITIO_NUM_REGS) {
+ if (reg < NITIO_NUM_REGS && chip < counter_dev->num_chips) {
spin_lock_irqsave(&counter_dev->regs_lock, flags);
- value = counter_dev->regs[reg];
+ value = counter_dev->regs[chip][reg];
spin_unlock_irqrestore(&counter_dev->regs_lock, flags);
}
return value;
@@ -302,6 +306,7 @@ static int ni_m_series_clock_src_select(const struct ni_gpct *counter,
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
unsigned int second_gate_reg = NITIO_GATE2_REG(cidx);
unsigned int clock_source = 0;
unsigned int src;
@@ -318,7 +323,7 @@ static int ni_m_series_clock_src_select(const struct ni_gpct *counter,
clock_source = NI_GPCT_TIMEBASE_2_CLOCK_SRC_BITS;
break;
case NI_M_TIMEBASE_3_CLK:
- if (counter_dev->regs[second_gate_reg] & GI_SRC_SUBSEL)
+ if (counter_dev->regs[chip][second_gate_reg] & GI_SRC_SUBSEL)
clock_source =
NI_GPCT_ANALOG_TRIGGER_OUT_CLOCK_SRC_BITS;
else
@@ -328,7 +333,7 @@ static int ni_m_series_clock_src_select(const struct ni_gpct *counter,
clock_source = NI_GPCT_LOGIC_LOW_CLOCK_SRC_BITS;
break;
case NI_M_NEXT_GATE_CLK:
- if (counter_dev->regs[second_gate_reg] & GI_SRC_SUBSEL)
+ if (counter_dev->regs[chip][second_gate_reg] & GI_SRC_SUBSEL)
clock_source = NI_GPCT_PXI_STAR_TRIGGER_CLOCK_SRC_BITS;
else
clock_source = NI_GPCT_NEXT_GATE_CLOCK_SRC_BITS;
@@ -721,6 +726,7 @@ static void ni_tio_set_source_subselect(struct ni_gpct *counter,
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
unsigned int second_gate_reg = NITIO_GATE2_REG(cidx);
if (counter_dev->variant != ni_gpct_variant_m_series)
@@ -729,18 +735,18 @@ static void ni_tio_set_source_subselect(struct ni_gpct *counter,
/* Gi_Source_Subselect is zero */
case NI_GPCT_NEXT_GATE_CLOCK_SRC_BITS:
case NI_GPCT_TIMEBASE_3_CLOCK_SRC_BITS:
- counter_dev->regs[second_gate_reg] &= ~GI_SRC_SUBSEL;
+ counter_dev->regs[chip][second_gate_reg] &= ~GI_SRC_SUBSEL;
break;
/* Gi_Source_Subselect is one */
case NI_GPCT_ANALOG_TRIGGER_OUT_CLOCK_SRC_BITS:
case NI_GPCT_PXI_STAR_TRIGGER_CLOCK_SRC_BITS:
- counter_dev->regs[second_gate_reg] |= GI_SRC_SUBSEL;
+ counter_dev->regs[chip][second_gate_reg] |= GI_SRC_SUBSEL;
break;
/* Gi_Source_Subselect doesn't matter */
default:
return;
}
- ni_tio_write(counter, counter_dev->regs[second_gate_reg],
+ ni_tio_write(counter, counter_dev->regs[chip][second_gate_reg],
second_gate_reg);
}
@@ -1116,6 +1122,7 @@ static int ni_tio_set_other_src(struct ni_gpct *counter, unsigned int index,
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
unsigned int abz_reg, shift, mask;
if (counter_dev->variant != ni_gpct_variant_m_series)
@@ -1141,9 +1148,9 @@ static int ni_tio_set_other_src(struct ni_gpct *counter, unsigned int index,
if (source > 0x1f)
source = 0x1f; /* Disable gate */
- counter_dev->regs[abz_reg] &= ~mask;
- counter_dev->regs[abz_reg] |= (source << shift) & mask;
- ni_tio_write(counter, counter_dev->regs[abz_reg], abz_reg);
+ counter_dev->regs[chip][abz_reg] &= ~mask;
+ counter_dev->regs[chip][abz_reg] |= (source << shift) & mask;
+ ni_tio_write(counter, counter_dev->regs[chip][abz_reg], abz_reg);
return 0;
}
@@ -1632,6 +1639,7 @@ int ni_tio_insn_read(struct comedi_device *dev,
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int channel = CR_CHAN(insn->chanspec);
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
int i;
for (i = 0; i < insn->n; i++) {
@@ -1640,10 +1648,12 @@ int ni_tio_insn_read(struct comedi_device *dev,
data[i] = ni_tio_read_sw_save_reg(dev, s);
break;
case 1:
- data[i] = counter_dev->regs[NITIO_LOADA_REG(cidx)];
+ data[i] =
+ counter_dev->regs[chip][NITIO_LOADA_REG(cidx)];
break;
case 2:
- data[i] = counter_dev->regs[NITIO_LOADB_REG(cidx)];
+ data[i] =
+ counter_dev->regs[chip][NITIO_LOADB_REG(cidx)];
break;
}
}
@@ -1670,6 +1680,7 @@ int ni_tio_insn_write(struct comedi_device *dev,
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int channel = CR_CHAN(insn->chanspec);
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
unsigned int load_reg;
if (insn->n < 1)
@@ -1690,14 +1701,15 @@ int ni_tio_insn_write(struct comedi_device *dev,
ni_tio_set_bits_transient(counter, NITIO_CMD_REG(cidx),
0, 0, GI_LOAD);
/* restore load reg */
- ni_tio_write(counter, counter_dev->regs[load_reg], load_reg);
+ ni_tio_write(counter, counter_dev->regs[chip][load_reg],
+ load_reg);
break;
case 1:
- counter_dev->regs[NITIO_LOADA_REG(cidx)] = data[0];
+ counter_dev->regs[chip][NITIO_LOADA_REG(cidx)] = data[0];
ni_tio_write(counter, data[0], NITIO_LOADA_REG(cidx));
break;
case 2:
- counter_dev->regs[NITIO_LOADB_REG(cidx)] = data[0];
+ counter_dev->regs[chip][NITIO_LOADB_REG(cidx)] = data[0];
ni_tio_write(counter, data[0], NITIO_LOADB_REG(cidx));
break;
default:
@@ -1711,11 +1723,12 @@ void ni_tio_init_counter(struct ni_gpct *counter)
{
struct ni_gpct_device *counter_dev = counter->counter_dev;
unsigned int cidx = counter->counter_index;
+ unsigned int chip = counter->chip_index;
ni_tio_reset_count_and_disarm(counter);
/* initialize counter registers */
- counter_dev->regs[NITIO_AUTO_INC_REG(cidx)] = 0x0;
+ counter_dev->regs[chip][NITIO_AUTO_INC_REG(cidx)] = 0x0;
ni_tio_write(counter, 0x0, NITIO_AUTO_INC_REG(cidx));
ni_tio_set_bits(counter, NITIO_CMD_REG(cidx),
@@ -1723,10 +1736,10 @@ void ni_tio_init_counter(struct ni_gpct *counter)
ni_tio_set_bits(counter, NITIO_MODE_REG(cidx), ~0, 0);
- counter_dev->regs[NITIO_LOADA_REG(cidx)] = 0x0;
+ counter_dev->regs[chip][NITIO_LOADA_REG(cidx)] = 0x0;
ni_tio_write(counter, 0x0, NITIO_LOADA_REG(cidx));
- counter_dev->regs[NITIO_LOADB_REG(cidx)] = 0x0;
+ counter_dev->regs[chip][NITIO_LOADB_REG(cidx)] = 0x0;
ni_tio_write(counter, 0x0, NITIO_LOADB_REG(cidx));
ni_tio_set_bits(counter, NITIO_INPUT_SEL_REG(cidx), ~0, 0);
@@ -1735,7 +1748,7 @@ void ni_tio_init_counter(struct ni_gpct *counter)
ni_tio_set_bits(counter, NITIO_CNT_MODE_REG(cidx), ~0, 0);
if (ni_tio_has_gate2_registers(counter_dev)) {
- counter_dev->regs[NITIO_GATE2_REG(cidx)] = 0x0;
+ counter_dev->regs[chip][NITIO_GATE2_REG(cidx)] = 0x0;
ni_tio_write(counter, 0x0, NITIO_GATE2_REG(cidx));
}
@@ -1776,9 +1789,16 @@ ni_gpct_device_construct(struct comedi_device *dev,
spin_lock_init(&counter_dev->regs_lock);
+ counter_dev->num_counters = num_counters;
+ counter_dev->num_chips = DIV_ROUND_UP(num_counters, counters_per_chip);
+
counter_dev->counters = kcalloc(num_counters, sizeof(*counter),
GFP_KERNEL);
- if (!counter_dev->counters) {
+ counter_dev->regs = kcalloc(counter_dev->num_chips,
+ sizeof(*counter_dev->regs), GFP_KERNEL);
+ if (!counter_dev->regs || !counter_dev->counters) {
+ kfree(counter_dev->regs);
+ kfree(counter_dev->counters);
kfree(counter_dev);
return NULL;
}
@@ -1790,8 +1810,6 @@ ni_gpct_device_construct(struct comedi_device *dev,
counter->counter_index = i % counters_per_chip;
spin_lock_init(&counter->lock);
}
- counter_dev->num_counters = num_counters;
- counter_dev->counters_per_chip = counters_per_chip;
return counter_dev;
}
@@ -1801,6 +1819,7 @@ void ni_gpct_device_destroy(struct ni_gpct_device *counter_dev)
{
if (!counter_dev)
return;
+ kfree(counter_dev->regs);
kfree(counter_dev->counters);
kfree(counter_dev);
}
diff --git a/drivers/staging/comedi/drivers/ni_tio.h b/drivers/staging/comedi/drivers/ni_tio.h
index 1e85d0a53715..e7b05718df9b 100644
--- a/drivers/staging/comedi/drivers/ni_tio.h
+++ b/drivers/staging/comedi/drivers/ni_tio.h
@@ -107,8 +107,8 @@ struct ni_gpct_device {
enum ni_gpct_variant variant;
struct ni_gpct *counters;
unsigned int num_counters;
- unsigned int counters_per_chip;
- unsigned int regs[NITIO_NUM_REGS];
+ unsigned int num_chips;
+ unsigned int (*regs)[NITIO_NUM_REGS]; /* [num_chips][NITIO_NUM_REGS] */
spinlock_t regs_lock; /* protects 'regs' */
const struct ni_route_tables *routing_tables; /* link to routes */
};
--
2.20.1
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