clk: Add clock driver for AXG
This patch adds a minimal clock driver for the Amlogic AXG SoC to handle
the basic gates and PLLs.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 821b586..a696245 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -9,7 +9,7 @@
obj-y += imx/
obj-y += tegra/
obj-$(CONFIG_ARCH_ASPEED) += aspeed/
-obj-$(CONFIG_ARCH_MESON) += clk_meson.o
+obj-$(CONFIG_ARCH_MESON) += clk_meson.o clk_meson_axg.o
obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
obj-$(CONFIG_ARCH_SOCFPGA) += altera/
obj-$(CONFIG_CLK_AT91) += at91/
diff --git a/drivers/clk/clk_meson_axg.c b/drivers/clk/clk_meson_axg.c
new file mode 100644
index 0000000..32cbf75
--- /dev/null
+++ b/drivers/clk/clk_meson_axg.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018 - Beniamino Galvani <b.galvani@gmail.com>
+ * (C) Copyright 2018 - BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+
+#include <common.h>
+#include <asm/arch/clock-axg.h>
+#include <asm/io.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <div64.h>
+#include <dt-bindings/clock/axg-clkc.h>
+#include "clk_meson.h"
+
+#define XTAL_RATE 24000000
+
+struct meson_clk {
+ struct regmap *map;
+};
+
+static ulong meson_clk_get_rate_by_id(struct clk *clk, unsigned long id);
+
+static struct meson_gate gates[] = {
+ /* Everything Else (EE) domain gates */
+ MESON_GATE(CLKID_SPICC0, HHI_GCLK_MPEG0, 8),
+ MESON_GATE(CLKID_I2C, HHI_GCLK_MPEG0, 9),
+ MESON_GATE(CLKID_UART0, HHI_GCLK_MPEG0, 13),
+ MESON_GATE(CLKID_SPICC1, HHI_GCLK_MPEG0, 15),
+ MESON_GATE(CLKID_SD_EMMC_B, HHI_GCLK_MPEG0, 25),
+ MESON_GATE(CLKID_SD_EMMC_C, HHI_GCLK_MPEG0, 26),
+ MESON_GATE(CLKID_ETH, HHI_GCLK_MPEG1, 3),
+ MESON_GATE(CLKID_UART1, HHI_GCLK_MPEG1, 16),
+
+ /* Always On (AO) domain gates */
+ MESON_GATE(CLKID_AO_I2C, HHI_GCLK_AO, 4),
+
+ /* PLL Gates */
+ /* CLKID_FCLK_DIV2 is critical for the SCPI Processor */
+ MESON_GATE(CLKID_MPLL2, HHI_MPLL_CNTL9, 14),
+ /* CLKID_CLK81 is critical for the system */
+
+ /* Peripheral Gates */
+ MESON_GATE(CLKID_SD_EMMC_B_CLK0, HHI_SD_EMMC_CLK_CNTL, 23),
+ MESON_GATE(CLKID_SD_EMMC_C_CLK0, HHI_NAND_CLK_CNTL, 7),
+};
+
+static int meson_set_gate(struct clk *clk, bool on)
+{
+ struct meson_clk *priv = dev_get_priv(clk->dev);
+ struct meson_gate *gate;
+
+ if (clk->id >= ARRAY_SIZE(gates))
+ return -ENOENT;
+
+ gate = &gates[clk->id];
+
+ if (gate->reg == 0)
+ return 0;
+
+ regmap_update_bits(priv->map, gate->reg,
+ BIT(gate->bit), on ? BIT(gate->bit) : 0);
+
+ return 0;
+}
+
+static int meson_clk_enable(struct clk *clk)
+{
+ return meson_set_gate(clk, true);
+}
+
+static int meson_clk_disable(struct clk *clk)
+{
+ return meson_set_gate(clk, false);
+}
+
+static unsigned long meson_clk81_get_rate(struct clk *clk)
+{
+ struct meson_clk *priv = dev_get_priv(clk->dev);
+ unsigned long parent_rate;
+ uint reg;
+ int parents[] = {
+ -1,
+ -1,
+ CLKID_FCLK_DIV7,
+ CLKID_MPLL1,
+ CLKID_MPLL2,
+ CLKID_FCLK_DIV4,
+ CLKID_FCLK_DIV3,
+ CLKID_FCLK_DIV5
+ };
+
+ /* mux */
+ regmap_read(priv->map, HHI_MPEG_CLK_CNTL, ®);
+ reg = (reg >> 12) & 7;
+
+ switch (reg) {
+ case 0:
+ parent_rate = XTAL_RATE;
+ break;
+ case 1:
+ return -ENOENT;
+ default:
+ parent_rate = meson_clk_get_rate_by_id(clk, parents[reg]);
+ }
+
+ /* divider */
+ regmap_read(priv->map, HHI_MPEG_CLK_CNTL, ®);
+ reg = reg & ((1 << 7) - 1);
+
+ return parent_rate / reg;
+}
+
+static long mpll_rate_from_params(unsigned long parent_rate,
+ unsigned long sdm,
+ unsigned long n2)
+{
+ unsigned long divisor = (SDM_DEN * n2) + sdm;
+
+ if (n2 < N2_MIN)
+ return -EINVAL;
+
+ return DIV_ROUND_UP_ULL((u64)parent_rate * SDM_DEN, divisor);
+}
+
+static struct parm meson_mpll0_parm[3] = {
+ {HHI_MPLL_CNTL7, 0, 14}, /* psdm */
+ {HHI_MPLL_CNTL7, 16, 9}, /* pn2 */
+};
+
+static struct parm meson_mpll1_parm[3] = {
+ {HHI_MPLL_CNTL8, 0, 14}, /* psdm */
+ {HHI_MPLL_CNTL8, 16, 9}, /* pn2 */
+};
+
+static struct parm meson_mpll2_parm[3] = {
+ {HHI_MPLL_CNTL9, 0, 14}, /* psdm */
+ {HHI_MPLL_CNTL9, 16, 9}, /* pn2 */
+};
+
+/*
+ * MultiPhase Locked Loops are outputs from a PLL with additional frequency
+ * scaling capabilities. MPLL rates are calculated as:
+ *
+ * f(N2_integer, SDM_IN ) = 2.0G/(N2_integer + SDM_IN/16384)
+ */
+static ulong meson_mpll_get_rate(struct clk *clk, unsigned long id)
+{
+ struct meson_clk *priv = dev_get_priv(clk->dev);
+ struct parm *psdm, *pn2;
+ unsigned long sdm, n2;
+ unsigned long parent_rate;
+ uint reg;
+
+ switch (id) {
+ case CLKID_MPLL0:
+ psdm = &meson_mpll0_parm[0];
+ pn2 = &meson_mpll0_parm[1];
+ break;
+ case CLKID_MPLL1:
+ psdm = &meson_mpll1_parm[0];
+ pn2 = &meson_mpll1_parm[1];
+ break;
+ case CLKID_MPLL2:
+ psdm = &meson_mpll2_parm[0];
+ pn2 = &meson_mpll2_parm[1];
+ break;
+ default:
+ return -ENOENT;
+ }
+
+ parent_rate = meson_clk_get_rate_by_id(clk, CLKID_FIXED_PLL);
+ if (IS_ERR_VALUE(parent_rate))
+ return parent_rate;
+
+ regmap_read(priv->map, psdm->reg_off, ®);
+ sdm = PARM_GET(psdm->width, psdm->shift, reg);
+
+ regmap_read(priv->map, pn2->reg_off, ®);
+ n2 = PARM_GET(pn2->width, pn2->shift, reg);
+
+ return mpll_rate_from_params(parent_rate, sdm, n2);
+}
+
+static struct parm meson_fixed_pll_parm[3] = {
+ {HHI_MPLL_CNTL, 0, 9}, /* pm */
+ {HHI_MPLL_CNTL, 9, 5}, /* pn */
+ {HHI_MPLL_CNTL, 16, 2}, /* pod */
+};
+
+static struct parm meson_sys_pll_parm[3] = {
+ {HHI_SYS_PLL_CNTL, 0, 9}, /* pm */
+ {HHI_SYS_PLL_CNTL, 9, 5}, /* pn */
+ {HHI_SYS_PLL_CNTL, 16, 2}, /* pod */
+};
+
+static ulong meson_pll_get_rate(struct clk *clk, unsigned long id)
+{
+ struct meson_clk *priv = dev_get_priv(clk->dev);
+ struct parm *pm, *pn, *pod;
+ unsigned long parent_rate_mhz = XTAL_RATE / 1000000;
+ u16 n, m, od;
+ uint reg;
+
+ switch (id) {
+ case CLKID_FIXED_PLL:
+ pm = &meson_fixed_pll_parm[0];
+ pn = &meson_fixed_pll_parm[1];
+ pod = &meson_fixed_pll_parm[2];
+ break;
+ case CLKID_SYS_PLL:
+ pm = &meson_sys_pll_parm[0];
+ pn = &meson_sys_pll_parm[1];
+ pod = &meson_sys_pll_parm[2];
+ break;
+ default:
+ return -ENOENT;
+ }
+
+ regmap_read(priv->map, pn->reg_off, ®);
+ n = PARM_GET(pn->width, pn->shift, reg);
+
+ regmap_read(priv->map, pm->reg_off, ®);
+ m = PARM_GET(pm->width, pm->shift, reg);
+
+ regmap_read(priv->map, pod->reg_off, ®);
+ od = PARM_GET(pod->width, pod->shift, reg);
+
+ return ((parent_rate_mhz * m / n) >> od) * 1000000;
+}
+
+static ulong meson_clk_get_rate_by_id(struct clk *clk, unsigned long id)
+{
+ ulong rate;
+
+ switch (id) {
+ case CLKID_FIXED_PLL:
+ case CLKID_SYS_PLL:
+ rate = meson_pll_get_rate(clk, id);
+ break;
+ case CLKID_FCLK_DIV2:
+ rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 2;
+ break;
+ case CLKID_FCLK_DIV3:
+ rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 3;
+ break;
+ case CLKID_FCLK_DIV4:
+ rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 4;
+ break;
+ case CLKID_FCLK_DIV5:
+ rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 5;
+ break;
+ case CLKID_FCLK_DIV7:
+ rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 7;
+ break;
+ case CLKID_MPLL0:
+ case CLKID_MPLL1:
+ case CLKID_MPLL2:
+ rate = meson_mpll_get_rate(clk, id);
+ break;
+ case CLKID_CLK81:
+ rate = meson_clk81_get_rate(clk);
+ break;
+ default:
+ if (gates[id].reg != 0) {
+ /* a clock gate */
+ rate = meson_clk81_get_rate(clk);
+ break;
+ }
+ return -ENOENT;
+ }
+
+ debug("clock %lu has rate %lu\n", id, rate);
+ return rate;
+}
+
+static ulong meson_clk_get_rate(struct clk *clk)
+{
+ return meson_clk_get_rate_by_id(clk, clk->id);
+}
+
+static int meson_clk_probe(struct udevice *dev)
+{
+ struct meson_clk *priv = dev_get_priv(dev);
+
+ priv->map = syscon_node_to_regmap(dev_get_parent(dev)->node);
+ if (IS_ERR(priv->map))
+ return PTR_ERR(priv->map);
+
+ debug("meson-clk-axg: probed\n");
+
+ return 0;
+}
+
+static struct clk_ops meson_clk_ops = {
+ .disable = meson_clk_disable,
+ .enable = meson_clk_enable,
+ .get_rate = meson_clk_get_rate,
+};
+
+static const struct udevice_id meson_clk_ids[] = {
+ { .compatible = "amlogic,axg-clkc" },
+ { }
+};
+
+U_BOOT_DRIVER(meson_clk_axg) = {
+ .name = "meson_clk_axg",
+ .id = UCLASS_CLK,
+ .of_match = meson_clk_ids,
+ .priv_auto_alloc_size = sizeof(struct meson_clk),
+ .ops = &meson_clk_ops,
+ .probe = meson_clk_probe,
+};