Added clock information and deprecated calibration support.
Signed-off-by: Srinivas Neeli <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
Changes in V9:
-Updated clock information in clock-names.
Changes in V8:
-None
Changes in V7:
-None
Changes in V6:
-Removed dtc warnings.
Changes in V5:
-Removed quotes and _clk suffix from clocknames.
Changes in V4:
- Deprecated calibrtion support
Changes in V3:
- New patch
---
.../devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
index bdb72d3ddf2a..9dfe2cc5966a 100644
--- a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
@@ -23,8 +23,15 @@ properties:
reg:
maxItems: 1
+ clocks:
+ maxItems: 1
+
+ clock-names:
+ items:
+ - const: rtc
+
interrupts:
- minItems: 2
+ maxItems: 2
interrupt-names:
items:
@@ -39,6 +46,7 @@ properties:
minimum: 0x1
maximum: 0x1FFFFF
default: 0x198233
+ deprecated: true
required:
- compatible
@@ -61,5 +69,7 @@ examples:
interrupts = <0 26 4>, <0 27 4>;
interrupt-names = "alarm", "sec";
calibration = <0x198233>;
+ clock-names = "rtc_clk";
+ clocks = <&rtc_clk>;
};
};
--
2.25.1
Zynqmp RTC controller has a calibration feature to compensate
time deviation due to input clock inaccuracy.
Set and get calibration API's are used for setting and getting
calibration value from the controller calibration register.
Signed-off-by: Srinivas Neeli <[email protected]>
---
Changes in V9:
-None
Changes in V8:
-None
Changes in V7:
-Removed calibration default value update from this patch.
Changes in V6:
-None
Changes in V5:
-None
Changes in V4:
-Updated MIN and MAX calibration values.
Changes in V3:
-Calculated tick_mult using crystal frequency.
-Calibration register updating based on crystal frequency in probe.
-Supressed MIN an MAX calibration values,Will send separate patch in future.
Changes in V2:
-Removed unused macro.
-Updated code with review comments.
---
drivers/rtc/rtc-zynqmp.c | 113 ++++++++++++++++++++++++++++++++-------
1 file changed, 94 insertions(+), 19 deletions(-)
diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c
index 5da33d760419..1dd389b891fe 100644
--- a/drivers/rtc/rtc-zynqmp.c
+++ b/drivers/rtc/rtc-zynqmp.c
@@ -6,6 +6,7 @@
*
*/
+#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
@@ -40,13 +41,19 @@
#define RTC_CALIB_MASK 0x1FFFFF
#define RTC_ALRM_MASK BIT(1)
#define RTC_MSEC 1000
+#define RTC_FR_MASK 0xF0000
+#define RTC_FR_MAX_TICKS 16
+#define RTC_PPB 1000000000LL
+#define RTC_MIN_OFFSET -32768000
+#define RTC_MAX_OFFSET 32767000
struct xlnx_rtc_dev {
struct rtc_device *rtc;
void __iomem *reg_base;
int alarm_irq;
int sec_irq;
- unsigned int calibval;
+ struct clk *rtc_clk;
+ unsigned int freq;
};
static int xlnx_rtc_set_time(struct device *dev, struct rtc_time *tm)
@@ -61,13 +68,6 @@ static int xlnx_rtc_set_time(struct device *dev, struct rtc_time *tm)
*/
new_time = rtc_tm_to_time64(tm) + 1;
- /*
- * Writing into calibration register will clear the Tick Counter and
- * force the next second to be signaled exactly in 1 second period
- */
- xrtcdev->calibval &= RTC_CALIB_MASK;
- writel(xrtcdev->calibval, (xrtcdev->reg_base + RTC_CALIB_WR));
-
writel(new_time, xrtcdev->reg_base + RTC_SET_TM_WR);
/*
@@ -173,15 +173,76 @@ static void xlnx_init_rtc(struct xlnx_rtc_dev *xrtcdev)
rtc_ctrl = readl(xrtcdev->reg_base + RTC_CTRL);
rtc_ctrl |= RTC_BATT_EN;
writel(rtc_ctrl, xrtcdev->reg_base + RTC_CTRL);
+}
- /*
- * Based on crystal freq of 33.330 KHz
- * set the seconds counter and enable, set fractions counter
- * to default value suggested as per design spec
- * to correct RTC delay in frequency over period of time.
+static int xlnx_rtc_read_offset(struct device *dev, long *offset)
+{
+ struct xlnx_rtc_dev *xrtcdev = dev_get_drvdata(dev);
+ unsigned long long rtc_ppb = RTC_PPB;
+ unsigned int tick_mult = do_div(rtc_ppb, xrtcdev->freq);
+ unsigned int calibval;
+ long offset_val;
+
+ calibval = readl(xrtcdev->reg_base + RTC_CALIB_RD);
+ /* Offset with seconds ticks */
+ offset_val = calibval & RTC_TICK_MASK;
+ offset_val = offset_val - RTC_CALIB_DEF;
+ offset_val = offset_val * tick_mult;
+
+ /* Offset with fractional ticks */
+ if (calibval & RTC_FR_EN)
+ offset_val += ((calibval & RTC_FR_MASK) >> RTC_FR_DATSHIFT)
+ * (tick_mult / RTC_FR_MAX_TICKS);
+ *offset = offset_val;
+
+ return 0;
+}
+
+static int xlnx_rtc_set_offset(struct device *dev, long offset)
+{
+ struct xlnx_rtc_dev *xrtcdev = dev_get_drvdata(dev);
+ unsigned long long rtc_ppb = RTC_PPB;
+ unsigned int tick_mult = do_div(rtc_ppb, xrtcdev->freq);
+ unsigned char fract_tick;
+ unsigned int calibval;
+ short int max_tick;
+ int fract_offset;
+
+ if (offset < RTC_MIN_OFFSET || offset > RTC_MAX_OFFSET)
+ return -ERANGE;
+
+ /* Number ticks for given offset */
+ max_tick = div_s64_rem(offset, tick_mult, &fract_offset);
+
+ /* Number fractional ticks for given offset */
+ if (fract_offset) {
+ if (fract_offset < 0) {
+ fract_offset = fract_offset + tick_mult;
+ max_tick--;
+ }
+ if (fract_offset > (tick_mult / RTC_FR_MAX_TICKS)) {
+ for (fract_tick = 1; fract_tick < 16; fract_tick++) {
+ if (fract_offset <=
+ (fract_tick *
+ (tick_mult / RTC_FR_MAX_TICKS)))
+ break;
+ }
+ }
+ }
+
+ /* Zynqmp RTC uses second and fractional tick
+ * counters for compensation
*/
- xrtcdev->calibval &= RTC_CALIB_MASK;
- writel(xrtcdev->calibval, (xrtcdev->reg_base + RTC_CALIB_WR));
+ calibval = max_tick + RTC_CALIB_DEF;
+
+ if (fract_tick)
+ calibval |= RTC_FR_EN;
+
+ calibval |= (fract_tick << RTC_FR_DATSHIFT);
+
+ writel(calibval, (xrtcdev->reg_base + RTC_CALIB_WR));
+
+ return 0;
}
static const struct rtc_class_ops xlnx_rtc_ops = {
@@ -190,6 +251,8 @@ static const struct rtc_class_ops xlnx_rtc_ops = {
.read_alarm = xlnx_rtc_read_alarm,
.set_alarm = xlnx_rtc_set_alarm,
.alarm_irq_enable = xlnx_rtc_alarm_irq_enable,
+ .read_offset = xlnx_rtc_read_offset,
+ .set_offset = xlnx_rtc_set_offset,
};
static irqreturn_t xlnx_rtc_interrupt(int irq, void *id)
@@ -255,10 +318,22 @@ static int xlnx_rtc_probe(struct platform_device *pdev)
return ret;
}
- ret = of_property_read_u32(pdev->dev.of_node, "calibration",
- &xrtcdev->calibval);
- if (ret)
- xrtcdev->calibval = RTC_CALIB_DEF;
+ /* Getting the rtc_clk info */
+ xrtcdev->rtc_clk = devm_clk_get_optional(&pdev->dev, "rtc_clk");
+ if (IS_ERR(xrtcdev->rtc_clk)) {
+ if (PTR_ERR(xrtcdev->rtc_clk) != -EPROBE_DEFER)
+ dev_warn(&pdev->dev, "Device clock not found.\n");
+ }
+ xrtcdev->freq = clk_get_rate(xrtcdev->rtc_clk);
+ if (!xrtcdev->freq) {
+ ret = of_property_read_u32(pdev->dev.of_node, "calibration",
+ &xrtcdev->freq);
+ if (ret)
+ xrtcdev->freq = RTC_CALIB_DEF;
+ }
+ ret = readl(xrtcdev->reg_base + RTC_CALIB_RD);
+ if (!ret)
+ writel(xrtcdev->freq, (xrtcdev->reg_base + RTC_CALIB_WR));
xlnx_init_rtc(xrtcdev);
--
2.25.1
As per RTC spec default calibration value is 0x7FFF.
We are in process to update the 0x7FFF as default value in
the next version of TRM.
Signed-off-by: Srinivas Neeli <[email protected]>
Acked-by: Peter Korsgaard <[email protected]>
---
Changes in V8
-None, just swapped 2/3 and 3/3 patches from V7.
Changes in V7:
-New patch
-TRM not updated yet, Internal design document contains 0x7FFF as
default value. TRM Will update in next release.
---
drivers/rtc/rtc-zynqmp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/rtc/rtc-zynqmp.c b/drivers/rtc/rtc-zynqmp.c
index f440bb52be92..5da33d760419 100644
--- a/drivers/rtc/rtc-zynqmp.c
+++ b/drivers/rtc/rtc-zynqmp.c
@@ -36,7 +36,7 @@
#define RTC_OSC_EN BIT(24)
#define RTC_BATT_EN BIT(31)
-#define RTC_CALIB_DEF 0x198233
+#define RTC_CALIB_DEF 0x7FFF
#define RTC_CALIB_MASK 0x1FFFFF
#define RTC_ALRM_MASK BIT(1)
#define RTC_MSEC 1000
--
2.25.1
On Fri, 24 Jun 2022 17:32:01 +0530, Srinivas Neeli wrote:
> Added clock information and deprecated calibration support.
>
> Signed-off-by: Srinivas Neeli <[email protected]>
> Reviewed-by: Rob Herring <[email protected]>
> ---
> Changes in V9:
> -Updated clock information in clock-names.
> Changes in V8:
> -None
> Changes in V7:
> -None
> Changes in V6:
> -Removed dtc warnings.
> Changes in V5:
> -Removed quotes and _clk suffix from clocknames.
> Changes in V4:
> - Deprecated calibrtion support
> Changes in V3:
> - New patch
> ---
> .../devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):
yamllint warnings/errors:
dtschema/dtc warnings/errors:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.example.dtb: rtc@ffa60000: clock-names:0: 'rtc' was expected
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
doc reference errors (make refcheckdocs):
See https://patchwork.ozlabs.org/patch/
This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.
If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:
pip3 install dtschema --upgrade
Please check and re-submit.
On 24/06/2022 14:02, Srinivas Neeli wrote:
> Added clock information and deprecated calibration support.
>
> Signed-off-by: Srinivas Neeli <[email protected]>
> Reviewed-by: Rob Herring <[email protected]>
> ---
> Changes in V9:
> -Updated clock information in clock-names.
> Changes in V8:
> -None
> Changes in V7:
> -None
> Changes in V6:
> -Removed dtc warnings.
> Changes in V5:
> -Removed quotes and _clk suffix from clocknames.
> Changes in V4:
> - Deprecated calibrtion support
> Changes in V3:
> - New patch
> ---
> .../devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
> index bdb72d3ddf2a..9dfe2cc5966a 100644
> --- a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
> @@ -23,8 +23,15 @@ properties:
> reg:
> maxItems: 1
>
> + clocks:
> + maxItems: 1
> +
> + clock-names:
> + items:
> + - const: rtc
> +
> interrupts:
> - minItems: 2
> + maxItems: 2
>
> interrupt-names:
> items:
> @@ -39,6 +46,7 @@ properties:
> minimum: 0x1
> maximum: 0x1FFFFF
> default: 0x198233
> + deprecated: true
>
> required:
> - compatible
> @@ -61,5 +69,7 @@ examples:
> interrupts = <0 26 4>, <0 27 4>;
> interrupt-names = "alarm", "sec";
> calibration = <0x198233>;
> + clock-names = "rtc_clk";
> + clocks = <&rtc_clk>;
Please test your bindings with `make dt_binding_check` before sending.
Best regards,
Krzysztof