[PATCH 3/3] clk: meson-g12a: add PCIE PLL clocks

Neil Armstrong
2019-03-07T14:15:09Z

Add the PCIe reference clock feeding the USB3 + PCIE combo PHY.

This PLL needs a very precise register sequence to permit to be locked,
thus using the specific clk-pll pcie ops.

The PLL is then followed by :
- a fixed /2 divider
- a 5-bit 1-based divider
- a final /2 divider

This reference clock is fixed to 100MHz, thus only a single PLL setup
is added.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
drivers/clk/meson/g12a.c | 118 +++++++++++++++++++++++++++++++++++++++
drivers/clk/meson/g12a.h | 5 +-
2 files changed, 122 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/meson/g12a.c b/drivers/clk/meson/g12a.c
index 80a7172df2a6..d382c21a29e5 100644
--- a/drivers/clk/meson/g12a.c
+++ b/drivers/clk/meson/g12a.c
@@ -614,6 +614,118 @@ static struct clk_regmap g12a_hifi_pll = {
},
};

+/*
+ * The Meson G12A PCIE PLL is fined tuned to deliver a very precise
+ * 100MHz reference clock for the PCIe Analog PHY, and thus requires
+ * a strict register sequence to enable the PLL.
+ */
+static const struct reg_sequence g12a_pcie_pll_init_regs[] = {
+ { .reg = HHI_PCIE_PLL_CNTL0, .def = 0x20090496 },
+ { .reg = HHI_PCIE_PLL_CNTL0, .def = 0x30090496 },
+ { .reg = HHI_PCIE_PLL_CNTL1, .def = 0x00000000 },
+ { .reg = HHI_PCIE_PLL_CNTL2, .def = 0x00001100 },
+ { .reg = HHI_PCIE_PLL_CNTL3, .def = 0x10058e00 },
+ { .reg = HHI_PCIE_PLL_CNTL4, .def = 0x000100c0 },
+ { .reg = HHI_PCIE_PLL_CNTL5, .def = 0x68000048 },
+ { .reg = HHI_PCIE_PLL_CNTL5, .def = 0x68000068, .delay_us = 20 },
+ { .reg = HHI_PCIE_PLL_CNTL4, .def = 0x008100c0, .delay_us = 10 },
+ { .reg = HHI_PCIE_PLL_CNTL0, .def = 0x34090496 },
+ { .reg = HHI_PCIE_PLL_CNTL0, .def = 0x14090496, .delay_us = 10 },
+ { .reg = HHI_PCIE_PLL_CNTL2, .def = 0x00001000 },
+};
+
+/* Keep a single entry table for recalc/round_rate() ops */
+static const struct pll_params_table g12a_pcie_pll_table[] = {
+ PLL_PARAMS(150, 1),
+ {0, 0},
+};
+
+static struct clk_regmap g12a_pcie_pll_dco = {
+ .data = &(struct meson_clk_pll_data){
+ .en = {
+ .reg_off = HHI_PCIE_PLL_CNTL0,
+ .shift = 28,
+ .width = 1,
+ },
+ .m = {
+ .reg_off = HHI_PCIE_PLL_CNTL0,
+ .shift = 0,
+ .width = 8,
+ },
+ .n = {
+ .reg_off = HHI_PCIE_PLL_CNTL0,
+ .shift = 10,
+ .width = 5,
+ },
+ .frac = {
+ .reg_off = HHI_PCIE_PLL_CNTL1,
+ .shift = 0,
+ .width = 12,
+ },
+ .l = {
+ .reg_off = HHI_PCIE_PLL_CNTL0,
+ .shift = 31,
+ .width = 1,
+ },
+ .rst = {
+ .reg_off = HHI_PCIE_PLL_CNTL0,
+ .shift = 29,
+ .width = 1,
+ },
+ .table = g12a_pcie_pll_table,
+ .init_regs = g12a_pcie_pll_init_regs,
+ .init_count = ARRAY_SIZE(g12a_pcie_pll_init_regs),
+ },
+ .hw.init = &(struct clk_init_data){
+ .name = "pcie_pll_dco",
+ .ops = &meson_clk_pcie_pll_ops,
+ .parent_names = (const char *[]){ IN_PREFIX "xtal" },
+ .num_parents = 1,
+ },
+};
+
+static struct clk_fixed_factor g12a_pcie_pll_dco_div2 = {
+ .mult = 1,
+ .div = 2,
+ .hw.init = &(struct clk_init_data){
+ .name = "pcie_pll_dco_div2",
+ .ops = &clk_fixed_factor_ops,
+ .parent_names = (const char *[]){ "pcie_pll_dco" },
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap g12a_pcie_pll_od = {
+ .data = &(struct clk_regmap_div_data){
+ .offset = HHI_PCIE_PLL_CNTL0,
+ .shift = 16,
+ .width = 5,
+ .flags = CLK_DIVIDER_ROUND_CLOSEST |
+ CLK_DIVIDER_ONE_BASED |
+ CLK_DIVIDER_ALLOW_ZERO,
+ },
+ .hw.init = &(struct clk_init_data){
+ .name = "pcie_pll_od",
+ .ops = &clk_regmap_divider_ops,
+ .parent_names = (const char *[]){ "pcie_pll_dco_div2" },
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_fixed_factor g12a_pcie_pll = {
+ .mult = 1,
+ .div = 2,
+ .hw.init = &(struct clk_init_data){
+ .name = "pcie_pll_pll",
+ .ops = &clk_fixed_factor_ops,
+ .parent_names = (const char *[]){ "pcie_pll_od" },
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
static struct clk_regmap g12a_hdmi_pll_dco = {
.data = &(struct meson_clk_pll_data){
.en = {
@@ -2499,6 +2611,10 @@ static struct clk_hw_onecell_data g12a_hw_onecell_data = {
[CLKID_CPU_CLK_AXI] = &g12a_cpu_clk_axi.hw,
[CLKID_CPU_CLK_TRACE_DIV] = &g12a_cpu_clk_trace_div.hw,
[CLKID_CPU_CLK_TRACE] = &g12a_cpu_clk_trace.hw,
+ [CLKID_PCIE_PLL_DCO] = &g12a_pcie_pll_dco.hw,
+ [CLKID_PCIE_PLL_DCO_DIV2] = &g12a_pcie_pll_dco_div2.hw,
+ [CLKID_PCIE_PLL_OD] = &g12a_pcie_pll_od.hw,
+ [CLKID_PCIE_PLL] = &g12a_pcie_pll.hw,
[NR_CLKS] = NULL,
},
.num = NR_CLKS,
@@ -2685,6 +2801,8 @@ static struct clk_regmap *const g12a_clk_regmaps[] = {
&g12a_cpu_clk_axi,
&g12a_cpu_clk_trace_div,
&g12a_cpu_clk_trace,
+ &g12a_pcie_pll_od,
+ &g12a_pcie_pll_dco,
};

static const struct meson_eeclkc_data g12a_clkc_data = {
diff --git a/drivers/clk/meson/g12a.h b/drivers/clk/meson/g12a.h
index 70aa469ca1cf..1393a09730a6 100644
--- a/drivers/clk/meson/g12a.h
+++ b/drivers/clk/meson/g12a.h
@@ -186,8 +186,11 @@
#define CLKID_CPU_CLK_AXI 195
#define CLKID_CPU_CLK_TRACE_DIV 196
#define CLKID_CPU_CLK_TRACE 197
+#define CLKID_PCIE_PLL_DCO 198
+#define CLKID_PCIE_PLL_DCO_DIV2 199
+#define CLKID_PCIE_PLL_OD 200

-#define NR_CLKS 198
+#define NR_CLKS 202

/* include the CLKIDs that have been made part of the DT binding */
#include <dt-bindings/clock/g12a-clkc.h>
--
2.20.1