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authorDinh Nguyen <dinguyen@kernel.org>2018-03-21 15:20:12 +0100
committerStephen Boyd <sboyd@kernel.org>2018-04-06 19:12:35 +0200
commit07afb8db7340f9b6051a26c5c28f2ce74148f6b5 (patch)
tree0832c3b259b1427d079c8c574a99f266dd63b8b0 /drivers/clk/socfpga/clk-pll-s10.c
parentdt-bindings: documentation: add clock bindings information for Stratix10 (diff)
downloadlinux-07afb8db7340f9b6051a26c5c28f2ce74148f6b5.tar.xz
linux-07afb8db7340f9b6051a26c5c28f2ce74148f6b5.zip
clk: socfpga: stratix10: add clock driver for Stratix10 platform
Add a clock driver for the Stratix10 SoC. The driver is similar to the Cyclone5/Arria10 platforms, with the exception that this driver only uses one single clock binding. Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Diffstat (limited to 'drivers/clk/socfpga/clk-pll-s10.c')
-rw-r--r--drivers/clk/socfpga/clk-pll-s10.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-pll-s10.c b/drivers/clk/socfpga/clk-pll-s10.c
new file mode 100644
index 000000000000..2d5d8b43727e
--- /dev/null
+++ b/drivers/clk/socfpga/clk-pll-s10.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017, Intel Corporation
+ */
+#include <linux/slab.h>
+#include <linux/clk-provider.h>
+
+#include "stratix10-clk.h"
+#include "clk.h"
+
+/* Clock Manager offsets */
+#define CLK_MGR_PLL_CLK_SRC_SHIFT 16
+#define CLK_MGR_PLL_CLK_SRC_MASK 0x3
+
+/* PLL Clock enable bits */
+#define SOCFPGA_PLL_POWER 0
+#define SOCFPGA_PLL_RESET_MASK 0x2
+#define SOCFPGA_PLL_REFDIV_MASK 0x00003F00
+#define SOCFPGA_PLL_REFDIV_SHIFT 8
+#define SOCFPGA_PLL_MDIV_MASK 0xFF000000
+#define SOCFPGA_PLL_MDIV_SHIFT 24
+#define SWCTRLBTCLKSEL_MASK 0x200
+#define SWCTRLBTCLKSEL_SHIFT 9
+
+#define SOCFPGA_BOOT_CLK "boot_clk"
+
+#define to_socfpga_clk(p) container_of(p, struct socfpga_pll, hw.hw)
+
+static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+ unsigned long mdiv;
+ unsigned long refdiv;
+ unsigned long reg;
+ unsigned long long vco_freq;
+
+ /* read VCO1 reg for numerator and denominator */
+ reg = readl(socfpgaclk->hw.reg);
+ refdiv = (reg & SOCFPGA_PLL_REFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;
+ vco_freq = (unsigned long long)parent_rate / refdiv;
+
+ /* Read mdiv and fdiv from the fdbck register */
+ reg = readl(socfpgaclk->hw.reg + 0x4);
+ mdiv = (reg & SOCFPGA_PLL_MDIV_MASK) >> SOCFPGA_PLL_MDIV_SHIFT;
+ vco_freq = (unsigned long long)parent_rate * (mdiv + 6);
+
+ return (unsigned long)vco_freq;
+}
+
+static unsigned long clk_boot_clk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+ u32 div = 1;
+
+ div = ((readl(socfpgaclk->hw.reg) &
+ SWCTRLBTCLKSEL_MASK) >>
+ SWCTRLBTCLKSEL_SHIFT);
+ div += 1;
+ return parent_rate /= div;
+}
+
+
+static u8 clk_pll_get_parent(struct clk_hw *hwclk)
+{
+ struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+ u32 pll_src;
+
+ pll_src = readl(socfpgaclk->hw.reg);
+ return (pll_src >> CLK_MGR_PLL_CLK_SRC_SHIFT) &
+ CLK_MGR_PLL_CLK_SRC_MASK;
+}
+
+static u8 clk_boot_get_parent(struct clk_hw *hwclk)
+{
+ struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+ u32 pll_src;
+
+ pll_src = readl(socfpgaclk->hw.reg);
+ return (pll_src >> SWCTRLBTCLKSEL_SHIFT) &
+ SWCTRLBTCLKSEL_MASK;
+}
+
+static int clk_pll_prepare(struct clk_hw *hwclk)
+{
+ struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+ u32 reg;
+
+ /* Bring PLL out of reset */
+ reg = readl(socfpgaclk->hw.reg);
+ reg |= SOCFPGA_PLL_RESET_MASK;
+ writel(reg, socfpgaclk->hw.reg);
+
+ return 0;
+}
+
+static struct clk_ops clk_pll_ops = {
+ .recalc_rate = clk_pll_recalc_rate,
+ .get_parent = clk_pll_get_parent,
+ .prepare = clk_pll_prepare,
+};
+
+static struct clk_ops clk_boot_ops = {
+ .recalc_rate = clk_boot_clk_recalc_rate,
+ .get_parent = clk_boot_get_parent,
+ .prepare = clk_pll_prepare,
+};
+
+struct clk *s10_register_pll(const char *name, const char * const *parent_names,
+ u8 num_parents, unsigned long flags,
+ void __iomem *reg, unsigned long offset)
+{
+ struct clk *clk;
+ struct socfpga_pll *pll_clk;
+ struct clk_init_data init;
+
+ pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
+ if (WARN_ON(!pll_clk))
+ return NULL;
+
+ pll_clk->hw.reg = reg + offset;
+
+ if (streq(name, SOCFPGA_BOOT_CLK))
+ init.ops = &clk_boot_ops;
+ else
+ init.ops = &clk_pll_ops;
+
+ init.name = name;
+ init.flags = flags;
+
+ init.num_parents = num_parents;
+ init.parent_names = parent_names;
+ pll_clk->hw.hw.init = &init;
+
+ pll_clk->hw.bit_idx = SOCFPGA_PLL_POWER;
+ clk_pll_ops.enable = clk_gate_ops.enable;
+ clk_pll_ops.disable = clk_gate_ops.disable;
+
+ clk = clk_register(NULL, &pll_clk->hw.hw);
+ if (WARN_ON(IS_ERR(clk))) {
+ kfree(pll_clk);
+ return NULL;
+ }
+ return clk;
+}