Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 161 insertions, 0 deletions

diff --git a/drivers/clk/sunxi-ng/ccu_sdm.c b/drivers/clk/sunxi-ng/ccu_sdm.c
new file mode 100644
index 0000000000..41937ed076
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_sdm.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2017 Chen-Yu Tsai <wens@csie.org>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+
+#include "ccu_sdm.h"
+
+bool ccu_sdm_helper_is_enabled(struct ccu_common *common,
+			       struct ccu_sdm_internal *sdm)
+{
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return false;
+
+	if (sdm->enable && !(readl(common->base + common->reg) & sdm->enable))
+		return false;
+
+	return !!(readl(common->base + sdm->tuning_reg) & sdm->tuning_enable);
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_is_enabled, SUNXI_CCU);
+
+void ccu_sdm_helper_enable(struct ccu_common *common,
+			   struct ccu_sdm_internal *sdm,
+			   unsigned long rate)
+{
+	unsigned long flags;
+	unsigned int i;
+	u32 reg;
+
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return;
+
+	/* Set the pattern */
+	for (i = 0; i < sdm->table_size; i++)
+		if (sdm->table[i].rate == rate)
+			writel(sdm->table[i].pattern,
+			       common->base + sdm->tuning_reg);
+
+	/* Make sure SDM is enabled */
+	spin_lock_irqsave(common->lock, flags);
+	reg = readl(common->base + sdm->tuning_reg);
+	writel(reg | sdm->tuning_enable, common->base + sdm->tuning_reg);
+	spin_unlock_irqrestore(common->lock, flags);
+
+	spin_lock_irqsave(common->lock, flags);
+	reg = readl(common->base + common->reg);
+	writel(reg | sdm->enable, common->base + common->reg);
+	spin_unlock_irqrestore(common->lock, flags);
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_enable, SUNXI_CCU);
+
+void ccu_sdm_helper_disable(struct ccu_common *common,
+			    struct ccu_sdm_internal *sdm)
+{
+	unsigned long flags;
+	u32 reg;
+
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return;
+
+	spin_lock_irqsave(common->lock, flags);
+	reg = readl(common->base + common->reg);
+	writel(reg & ~sdm->enable, common->base + common->reg);
+	spin_unlock_irqrestore(common->lock, flags);
+
+	spin_lock_irqsave(common->lock, flags);
+	reg = readl(common->base + sdm->tuning_reg);
+	writel(reg & ~sdm->tuning_enable, common->base + sdm->tuning_reg);
+	spin_unlock_irqrestore(common->lock, flags);
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_disable, SUNXI_CCU);
+
+/*
+ * Sigma delta modulation provides a way to do fractional-N frequency
+ * synthesis, in essence allowing the PLL to output any frequency
+ * within its operational range. On earlier SoCs such as the A10/A20,
+ * some PLLs support this. On later SoCs, all PLLs support this.
+ *
+ * The datasheets do not explain what the "wave top" and "wave bottom"
+ * parameters mean or do, nor how to calculate the effective output
+ * frequency. The only examples (and real world usage) are for the audio
+ * PLL to generate 24.576 and 22.5792 MHz clock rates used by the audio
+ * peripherals. The author lacks the underlying domain knowledge to
+ * pursue this.
+ *
+ * The goal and function of the following code is to support the two
+ * clock rates used by the audio subsystem, allowing for proper audio
+ * playback and capture without any pitch or speed changes.
+ */
+bool ccu_sdm_helper_has_rate(struct ccu_common *common,
+			     struct ccu_sdm_internal *sdm,
+			     unsigned long rate)
+{
+	unsigned int i;
+
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return false;
+
+	for (i = 0; i < sdm->table_size; i++)
+		if (sdm->table[i].rate == rate)
+			return true;
+
+	return false;
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_has_rate, SUNXI_CCU);
+
+unsigned long ccu_sdm_helper_read_rate(struct ccu_common *common,
+				       struct ccu_sdm_internal *sdm,
+				       u32 m, u32 n)
+{
+	unsigned int i;
+	u32 reg;
+
+	pr_debug("%s: Read sigma-delta modulation setting\n",
+		 clk_hw_get_name(&common->hw));
+
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return 0;
+
+	pr_debug("%s: clock is sigma-delta modulated\n",
+		 clk_hw_get_name(&common->hw));
+
+	reg = readl(common->base + sdm->tuning_reg);
+
+	pr_debug("%s: pattern reg is 0x%x",
+		 clk_hw_get_name(&common->hw), reg);
+
+	for (i = 0; i < sdm->table_size; i++)
+		if (sdm->table[i].pattern == reg &&
+		    sdm->table[i].m == m && sdm->table[i].n == n)
+			return sdm->table[i].rate;
+
+	/* We can't calculate the effective clock rate, so just fail. */
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_read_rate, SUNXI_CCU);
+
+int ccu_sdm_helper_get_factors(struct ccu_common *common,
+			       struct ccu_sdm_internal *sdm,
+			       unsigned long rate,
+			       unsigned long *m, unsigned long *n)
+{
+	unsigned int i;
+
+	if (!(common->features & CCU_FEATURE_SIGMA_DELTA_MOD))
+		return -EINVAL;
+
+	for (i = 0; i < sdm->table_size; i++)
+		if (sdm->table[i].rate == rate) {
+			*m = sdm->table[i].m;
+			*n = sdm->table[i].n;
+			return 0;
+		}
+
+	/* nothing found */
+	return -EINVAL;
+}
+EXPORT_SYMBOL_NS_GPL(ccu_sdm_helper_get_factors, SUNXI_CCU);