This is a note to let you know that I've just added the patch titled
clocking-wizard: Support higher frequency accuracy
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
clocking-wizard-support-higher-frequency-accuracy.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 73c4d4f5ed37557ff69a04021aae626425913f0e
Author: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxx>
Date: Mon Mar 27 11:56:37 2023 +0530
clocking-wizard: Support higher frequency accuracy
[ Upstream commit 595c88cda65d30c6b36277c232193295a45406dc ]
Change the multipliers and divisors to support a higher
frequency accuracy if there is only one output.
Currently only O is changed now we are changing M, D and O.
For multiple output case the earlier behavior is retained.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxx>
Link: https://lore.kernel.org/r/20230327062637.22237-1-shubhrajyoti.datta@xxxxxxx
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Stable-dep-of: b1356ed1a446 ("clk: clocking-wizard: check return value of devm_kasprintf()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/clk/xilinx/clk-xlnx-clock-wizard.c b/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
index 4a23583933bcc..5c362c622a866 100644
--- a/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
+++ b/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
@@ -8,12 +8,14 @@
*
*/
+#include <linux/bitfield.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/math64.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/iopoll.h>
@@ -37,6 +39,7 @@
#define WZRD_CLKOUT_DIVIDE_MASK (0xff << WZRD_DIVCLK_DIVIDE_SHIFT)
#define WZRD_CLKOUT_FRAC_SHIFT 8
#define WZRD_CLKOUT_FRAC_MASK 0x3ff
+#define WZRD_CLKOUT0_FRAC_MASK GENMASK(17, 8)
#define WZRD_DR_MAX_INT_DIV_VALUE 255
#define WZRD_DR_STATUS_REG_OFFSET 0x04
@@ -49,6 +52,22 @@
#define WZRD_USEC_POLL 10
#define WZRD_TIMEOUT_POLL 1000
+
+/* Divider limits, from UG572 Table 3-4 for Ultrascale+ */
+#define DIV_O 0x01
+#define DIV_ALL 0x03
+
+#define WZRD_M_MIN 2
+#define WZRD_M_MAX 128
+#define WZRD_D_MIN 1
+#define WZRD_D_MAX 106
+#define WZRD_VCO_MIN 800000000
+#define WZRD_VCO_MAX 1600000000
+#define WZRD_O_MIN 1
+#define WZRD_O_MAX 128
+#define WZRD_MIN_ERR 20000
+#define WZRD_FRAC_POINTS 1000
+
/* Get the mask from width */
#define div_mask(width) ((1 << (width)) - 1)
@@ -97,6 +116,9 @@ struct clk_wzrd {
* @width: width of the divider bit field
* @flags: clk_wzrd divider flags
* @table: array of value/divider pairs, last entry should have div = 0
+ * @m: value of the multiplier
+ * @d: value of the common divider
+ * @o: value of the leaf divider
* @lock: register lock
*/
struct clk_wzrd_divider {
@@ -107,6 +129,9 @@ struct clk_wzrd_divider {
u8 width;
u8 flags;
const struct clk_div_table *table;
+ u32 m;
+ u32 d;
+ u32 o;
spinlock_t *lock; /* divider lock */
};
@@ -198,12 +223,155 @@ static long clk_wzrd_round_rate(struct clk_hw *hw, unsigned long rate,
return *prate / div;
}
+static int clk_wzrd_get_divisors(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
+ unsigned long vco_freq, freq, diff;
+ u32 m, d, o;
+
+ for (m = WZRD_M_MIN; m <= WZRD_M_MAX; m++) {
+ for (d = WZRD_D_MIN; d <= WZRD_D_MAX; d++) {
+ vco_freq = DIV_ROUND_CLOSEST((parent_rate * m), d);
+ if (vco_freq >= WZRD_VCO_MIN && vco_freq <= WZRD_VCO_MAX) {
+ for (o = WZRD_O_MIN; o <= WZRD_O_MAX; o++) {
+ freq = DIV_ROUND_CLOSEST_ULL(vco_freq, o);
+ diff = abs(freq - rate);
+
+ if (diff < WZRD_MIN_ERR) {
+ divider->m = m;
+ divider->d = d;
+ divider->o = o;
+ return 0;
+ }
+ }
+ }
+ }
+ }
+ return -EBUSY;
+}
+
+static int clk_wzrd_dynamic_all_nolock(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
+ unsigned long vco_freq, rate_div, clockout0_div;
+ u32 reg, pre, value, f;
+ int err;
+
+ err = clk_wzrd_get_divisors(hw, rate, parent_rate);
+ if (err)
+ return err;
+
+ vco_freq = DIV_ROUND_CLOSEST(parent_rate * divider->m, divider->d);
+ rate_div = DIV_ROUND_CLOSEST_ULL((vco_freq * WZRD_FRAC_POINTS), rate);
+
+ clockout0_div = div_u64(rate_div, WZRD_FRAC_POINTS);
+
+ pre = DIV_ROUND_CLOSEST_ULL(vco_freq * WZRD_FRAC_POINTS, rate);
+ f = (pre - (clockout0_div * WZRD_FRAC_POINTS));
+ f &= WZRD_CLKOUT_FRAC_MASK;
+
+ reg = FIELD_PREP(WZRD_CLKOUT_DIVIDE_MASK, clockout0_div) |
+ FIELD_PREP(WZRD_CLKOUT0_FRAC_MASK, f);
+
+ writel(reg, divider->base + WZRD_CLK_CFG_REG(2));
+ /* Set divisor and clear phase offset */
+ reg = FIELD_PREP(WZRD_CLKFBOUT_MULT_MASK, divider->m) |
+ FIELD_PREP(WZRD_DIVCLK_DIVIDE_MASK, divider->d);
+ writel(reg, divider->base + WZRD_CLK_CFG_REG(0));
+ writel(divider->o, divider->base + WZRD_CLK_CFG_REG(2));
+ writel(0, divider->base + WZRD_CLK_CFG_REG(3));
+ /* Check status register */
+ err = readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET, value,
+ value & WZRD_DR_LOCK_BIT_MASK,
+ WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
+ if (err)
+ return -ETIMEDOUT;
+
+ /* Initiate reconfiguration */
+ writel(WZRD_DR_BEGIN_DYNA_RECONF,
+ divider->base + WZRD_DR_INIT_REG_OFFSET);
+
+ /* Check status register */
+ return readl_poll_timeout(divider->base + WZRD_DR_STATUS_REG_OFFSET, value,
+ value & WZRD_DR_LOCK_BIT_MASK,
+ WZRD_USEC_POLL, WZRD_TIMEOUT_POLL);
+}
+
+static int clk_wzrd_dynamic_all(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
+ unsigned long flags = 0;
+ int ret;
+
+ spin_lock_irqsave(divider->lock, flags);
+
+ ret = clk_wzrd_dynamic_all_nolock(hw, rate, parent_rate);
+
+ spin_unlock_irqrestore(divider->lock, flags);
+
+ return ret;
+}
+
+static unsigned long clk_wzrd_recalc_rate_all(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
+ u32 m, d, o, div, reg, f;
+
+ reg = readl(divider->base + WZRD_CLK_CFG_REG(0));
+ d = FIELD_GET(WZRD_DIVCLK_DIVIDE_MASK, reg);
+ m = FIELD_GET(WZRD_CLKFBOUT_MULT_MASK, reg);
+ reg = readl(divider->base + WZRD_CLK_CFG_REG(2));
+ o = FIELD_GET(WZRD_DIVCLK_DIVIDE_MASK, reg);
+ f = FIELD_GET(WZRD_CLKOUT0_FRAC_MASK, reg);
+
+ div = DIV_ROUND_CLOSEST(d * (WZRD_FRAC_POINTS * o + f), WZRD_FRAC_POINTS);
+ return divider_recalc_rate(hw, parent_rate * m, div, divider->table,
+ divider->flags, divider->width);
+}
+
+static long clk_wzrd_round_rate_all(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ struct clk_wzrd_divider *divider = to_clk_wzrd_divider(hw);
+ unsigned long int_freq;
+ u32 m, d, o, div, f;
+ int err;
+
+ err = clk_wzrd_get_divisors(hw, rate, *prate);
+ if (err)
+ return err;
+
+ m = divider->m;
+ d = divider->d;
+ o = divider->o;
+
+ div = d * o;
+ int_freq = divider_recalc_rate(hw, *prate * m, div, divider->table,
+ divider->flags, divider->width);
+
+ if (rate > int_freq) {
+ f = DIV_ROUND_CLOSEST_ULL(rate * WZRD_FRAC_POINTS, int_freq);
+ rate = DIV_ROUND_CLOSEST(int_freq * f, WZRD_FRAC_POINTS);
+ }
+ return rate;
+}
+
static const struct clk_ops clk_wzrd_clk_divider_ops = {
.round_rate = clk_wzrd_round_rate,
.set_rate = clk_wzrd_dynamic_reconfig,
.recalc_rate = clk_wzrd_recalc_rate,
};
+static const struct clk_ops clk_wzrd_clk_div_all_ops = {
+ .round_rate = clk_wzrd_round_rate_all,
+ .set_rate = clk_wzrd_dynamic_all,
+ .recalc_rate = clk_wzrd_recalc_rate_all,
+};
+
static unsigned long clk_wzrd_recalc_ratef(struct clk_hw *hw,
unsigned long parent_rate)
{
@@ -280,7 +448,7 @@ static struct clk *clk_wzrd_register_divf(struct device *dev,
void __iomem *base, u16 offset,
u8 shift, u8 width,
u8 clk_divider_flags,
- const struct clk_div_table *table,
+ u32 div_type,
spinlock_t *lock)
{
struct clk_wzrd_divider *div;
@@ -307,7 +475,6 @@ static struct clk *clk_wzrd_register_divf(struct device *dev,
div->flags = clk_divider_flags;
div->lock = lock;
div->hw.init = &init;
- div->table = table;
hw = &div->hw;
ret = devm_clk_hw_register(dev, hw);
@@ -324,7 +491,7 @@ static struct clk *clk_wzrd_register_divider(struct device *dev,
void __iomem *base, u16 offset,
u8 shift, u8 width,
u8 clk_divider_flags,
- const struct clk_div_table *table,
+ u32 div_type,
spinlock_t *lock)
{
struct clk_wzrd_divider *div;
@@ -337,7 +504,12 @@ static struct clk *clk_wzrd_register_divider(struct device *dev,
return ERR_PTR(-ENOMEM);
init.name = name;
- init.ops = &clk_wzrd_clk_divider_ops;
+ if (clk_divider_flags & CLK_DIVIDER_READ_ONLY)
+ init.ops = &clk_divider_ro_ops;
+ else if (div_type == DIV_O)
+ init.ops = &clk_wzrd_clk_divider_ops;
+ else
+ init.ops = &clk_wzrd_clk_div_all_ops;
init.flags = flags;
init.parent_names = &parent_name;
init.num_parents = 1;
@@ -349,7 +521,6 @@ static struct clk *clk_wzrd_register_divider(struct device *dev,
div->flags = clk_divider_flags;
div->lock = lock;
div->hw.init = &init;
- div->table = table;
hw = &div->hw;
ret = devm_clk_hw_register(dev, hw);
@@ -425,6 +596,7 @@ static int clk_wzrd_probe(struct platform_device *pdev)
const char *clk_name;
void __iomem *ctrl_reg;
struct clk_wzrd *clk_wzrd;
+ const char *clkout_name;
struct device_node *np = pdev->dev.of_node;
int nr_outputs;
unsigned long flags = 0;
@@ -469,6 +641,26 @@ static int clk_wzrd_probe(struct platform_device *pdev)
goto err_disable_clk;
}
+ ret = of_property_read_u32(np, "xlnx,nr-outputs", &nr_outputs);
+ if (ret || nr_outputs > WZRD_NUM_OUTPUTS) {
+ ret = -EINVAL;
+ goto err_disable_clk;
+ }
+
+ clkout_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_out0", dev_name(&pdev->dev));
+ if (nr_outputs == 1) {
+ clk_wzrd->clkout[0] = clk_wzrd_register_divider
+ (&pdev->dev, clkout_name,
+ __clk_get_name(clk_wzrd->clk_in1), 0,
+ clk_wzrd->base, WZRD_CLK_CFG_REG(3),
+ WZRD_CLKOUT_DIVIDE_SHIFT,
+ WZRD_CLKOUT_DIVIDE_WIDTH,
+ CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
+ DIV_ALL, &clkwzrd_lock);
+
+ goto out;
+ }
+
reg = readl(clk_wzrd->base + WZRD_CLK_CFG_REG(0));
reg_f = reg & WZRD_CLKFBOUT_FRAC_MASK;
reg_f = reg_f >> WZRD_CLKFBOUT_FRAC_SHIFT;
@@ -476,20 +668,11 @@ static int clk_wzrd_probe(struct platform_device *pdev)
reg = reg & WZRD_CLKFBOUT_MULT_MASK;
reg = reg >> WZRD_CLKFBOUT_MULT_SHIFT;
mult = (reg * 1000) + reg_f;
- clk_name = kasprintf(GFP_KERNEL, "%s_mul", dev_name(&pdev->dev));
+ clk_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_mul", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_disable_clk;
}
-
- ret = of_property_read_u32(np, "xlnx,nr-outputs", &nr_outputs);
- if (ret || nr_outputs > WZRD_NUM_OUTPUTS) {
- ret = -EINVAL;
- goto err_disable_clk;
- }
- if (nr_outputs == 1)
- flags = CLK_SET_RATE_PARENT;
-
clk_wzrd->clks_internal[wzrd_clk_mul] = clk_register_fixed_factor
(&pdev->dev, clk_name,
__clk_get_name(clk_wzrd->clk_in1),
@@ -500,7 +683,7 @@ static int clk_wzrd_probe(struct platform_device *pdev)
goto err_disable_clk;
}
- clk_name = kasprintf(GFP_KERNEL, "%s_mul_div", dev_name(&pdev->dev));
+ clk_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_mul_div", dev_name(&pdev->dev));
if (!clk_name) {
ret = -ENOMEM;
goto err_rm_int_clk;
@@ -521,9 +704,8 @@ static int clk_wzrd_probe(struct platform_device *pdev)
/* register div per output */
for (i = nr_outputs - 1; i >= 0 ; i--) {
- const char *clkout_name;
-
- clkout_name = kasprintf(GFP_KERNEL, "%s_out%d", dev_name(&pdev->dev), i);
+ clkout_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+ "%s_out%d", dev_name(&pdev->dev), i);
if (!clkout_name) {
ret = -ENOMEM;
goto err_rm_int_clk;
@@ -537,7 +719,7 @@ static int clk_wzrd_probe(struct platform_device *pdev)
WZRD_CLKOUT_DIVIDE_SHIFT,
WZRD_CLKOUT_DIVIDE_WIDTH,
CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
- NULL, &clkwzrd_lock);
+ DIV_O, &clkwzrd_lock);
else
clk_wzrd->clkout[i] = clk_wzrd_register_divider
(&pdev->dev, clkout_name,
@@ -546,7 +728,7 @@ static int clk_wzrd_probe(struct platform_device *pdev)
WZRD_CLKOUT_DIVIDE_SHIFT,
WZRD_CLKOUT_DIVIDE_WIDTH,
CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO,
- NULL, &clkwzrd_lock);
+ DIV_O, &clkwzrd_lock);
if (IS_ERR(clk_wzrd->clkout[i])) {
int j;
@@ -559,8 +741,7 @@ static int clk_wzrd_probe(struct platform_device *pdev)
}
}
- kfree(clk_name);
-
+out:
clk_wzrd->clk_data.clks = clk_wzrd->clkout;
clk_wzrd->clk_data.clk_num = ARRAY_SIZE(clk_wzrd->clkout);
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_wzrd->clk_data);
@@ -585,7 +766,6 @@ static int clk_wzrd_probe(struct platform_device *pdev)
err_rm_int_clks:
clk_unregister(clk_wzrd->clks_internal[1]);
err_rm_int_clk:
- kfree(clk_name);
clk_unregister(clk_wzrd->clks_internal[0]);
err_disable_clk:
clk_disable_unprepare(clk_wzrd->axi_clk);
