Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / clk / socfpga / clk-gate.c
diff --git a/kernel/drivers/clk/socfpga/clk-gate.c b/kernel/drivers/clk/socfpga/clk-gate.c
new file mode 100644 (file)
index 0000000..dd3a78c
--- /dev/null
@@ -0,0 +1,262 @@
+/*
+ *  Copyright 2011-2012 Calxeda, Inc.
+ *  Copyright (C) 2012-2013 Altera Corporation <www.altera.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Based from clk-highbank.c
+ *
+ */
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include "clk.h"
+
+#define SOCFPGA_L4_MP_CLK              "l4_mp_clk"
+#define SOCFPGA_L4_SP_CLK              "l4_sp_clk"
+#define SOCFPGA_NAND_CLK               "nand_clk"
+#define SOCFPGA_NAND_X_CLK             "nand_x_clk"
+#define SOCFPGA_MMC_CLK                        "sdmmc_clk"
+#define SOCFPGA_GPIO_DB_CLK_OFFSET     0xA8
+
+#define streq(a, b) (strcmp((a), (b)) == 0)
+
+#define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
+
+/* SDMMC Group for System Manager defines */
+#define SYSMGR_SDMMCGRP_CTRL_OFFSET    0x108
+#define SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel) \
+       ((((smplsel) & 0x7) << 3) | (((drvsel) & 0x7) << 0))
+
+static u8 socfpga_clk_get_parent(struct clk_hw *hwclk)
+{
+       u32 l4_src;
+       u32 perpll_src;
+
+       if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
+               l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+               return l4_src &= 0x1;
+       }
+       if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
+               l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+               return !!(l4_src & 2);
+       }
+
+       perpll_src = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+       if (streq(hwclk->init->name, SOCFPGA_MMC_CLK))
+               return perpll_src &= 0x3;
+       if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
+                       streq(hwclk->init->name, SOCFPGA_NAND_X_CLK))
+                       return (perpll_src >> 2) & 3;
+
+       /* QSPI clock */
+       return (perpll_src >> 4) & 3;
+
+}
+
+static int socfpga_clk_set_parent(struct clk_hw *hwclk, u8 parent)
+{
+       u32 src_reg;
+
+       if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
+               src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+               src_reg &= ~0x1;
+               src_reg |= parent;
+               writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
+       } else if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
+               src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+               src_reg &= ~0x2;
+               src_reg |= (parent << 1);
+               writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
+       } else {
+               src_reg = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+               if (streq(hwclk->init->name, SOCFPGA_MMC_CLK)) {
+                       src_reg &= ~0x3;
+                       src_reg |= parent;
+               } else if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
+                       streq(hwclk->init->name, SOCFPGA_NAND_X_CLK)) {
+                       src_reg &= ~0xC;
+                       src_reg |= (parent << 2);
+               } else {/* QSPI clock */
+                       src_reg &= ~0x30;
+                       src_reg |= (parent << 4);
+               }
+               writel(src_reg, clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+       }
+
+       return 0;
+}
+
+static unsigned long socfpga_clk_recalc_rate(struct clk_hw *hwclk,
+       unsigned long parent_rate)
+{
+       struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
+       u32 div = 1, val;
+
+       if (socfpgaclk->fixed_div)
+               div = socfpgaclk->fixed_div;
+       else if (socfpgaclk->div_reg) {
+               val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
+               val &= div_mask(socfpgaclk->width);
+               /* Check for GPIO_DB_CLK by its offset */
+               if ((int) socfpgaclk->div_reg & SOCFPGA_GPIO_DB_CLK_OFFSET)
+                       div = val + 1;
+               else
+                       div = (1 << val);
+       }
+
+       return parent_rate / div;
+}
+
+static int socfpga_clk_prepare(struct clk_hw *hwclk)
+{
+       struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
+       struct regmap *sys_mgr_base_addr;
+       int i;
+       u32 hs_timing;
+       u32 clk_phase[2];
+
+       if (socfpgaclk->clk_phase[0] || socfpgaclk->clk_phase[1]) {
+               sys_mgr_base_addr = syscon_regmap_lookup_by_compatible("altr,sys-mgr");
+               if (IS_ERR(sys_mgr_base_addr)) {
+                       pr_err("%s: failed to find altr,sys-mgr regmap!\n", __func__);
+                       return -EINVAL;
+               }
+
+               for (i = 0; i < 2; i++) {
+                       switch (socfpgaclk->clk_phase[i]) {
+                       case 0:
+                               clk_phase[i] = 0;
+                               break;
+                       case 45:
+                               clk_phase[i] = 1;
+                               break;
+                       case 90:
+                               clk_phase[i] = 2;
+                               break;
+                       case 135:
+                               clk_phase[i] = 3;
+                               break;
+                       case 180:
+                               clk_phase[i] = 4;
+                               break;
+                       case 225:
+                               clk_phase[i] = 5;
+                               break;
+                       case 270:
+                               clk_phase[i] = 6;
+                               break;
+                       case 315:
+                               clk_phase[i] = 7;
+                               break;
+                       default:
+                               clk_phase[i] = 0;
+                               break;
+                       }
+               }
+               hs_timing = SYSMGR_SDMMC_CTRL_SET(clk_phase[0], clk_phase[1]);
+               regmap_write(sys_mgr_base_addr, SYSMGR_SDMMCGRP_CTRL_OFFSET,
+                       hs_timing);
+       }
+       return 0;
+}
+
+static struct clk_ops gateclk_ops = {
+       .prepare = socfpga_clk_prepare,
+       .recalc_rate = socfpga_clk_recalc_rate,
+       .get_parent = socfpga_clk_get_parent,
+       .set_parent = socfpga_clk_set_parent,
+};
+
+static void __init __socfpga_gate_init(struct device_node *node,
+       const struct clk_ops *ops)
+{
+       u32 clk_gate[2];
+       u32 div_reg[3];
+       u32 clk_phase[2];
+       u32 fixed_div;
+       struct clk *clk;
+       struct socfpga_gate_clk *socfpga_clk;
+       const char *clk_name = node->name;
+       const char *parent_name[SOCFPGA_MAX_PARENTS];
+       struct clk_init_data init;
+       int rc;
+       int i = 0;
+
+       socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
+       if (WARN_ON(!socfpga_clk))
+               return;
+
+       rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2);
+       if (rc)
+               clk_gate[0] = 0;
+
+       if (clk_gate[0]) {
+               socfpga_clk->hw.reg = clk_mgr_base_addr + clk_gate[0];
+               socfpga_clk->hw.bit_idx = clk_gate[1];
+
+               gateclk_ops.enable = clk_gate_ops.enable;
+               gateclk_ops.disable = clk_gate_ops.disable;
+       }
+
+       rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
+       if (rc)
+               socfpga_clk->fixed_div = 0;
+       else
+               socfpga_clk->fixed_div = fixed_div;
+
+       rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
+       if (!rc) {
+               socfpga_clk->div_reg = clk_mgr_base_addr + div_reg[0];
+               socfpga_clk->shift = div_reg[1];
+               socfpga_clk->width = div_reg[2];
+       } else {
+               socfpga_clk->div_reg = 0;
+       }
+
+       rc = of_property_read_u32_array(node, "clk-phase", clk_phase, 2);
+       if (!rc) {
+               socfpga_clk->clk_phase[0] = clk_phase[0];
+               socfpga_clk->clk_phase[1] = clk_phase[1];
+       }
+
+       of_property_read_string(node, "clock-output-names", &clk_name);
+
+       init.name = clk_name;
+       init.ops = ops;
+       init.flags = 0;
+       while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
+                       of_clk_get_parent_name(node, i)) != NULL)
+               i++;
+
+       init.parent_names = parent_name;
+       init.num_parents = i;
+       socfpga_clk->hw.hw.init = &init;
+
+       clk = clk_register(NULL, &socfpga_clk->hw.hw);
+       if (WARN_ON(IS_ERR(clk))) {
+               kfree(socfpga_clk);
+               return;
+       }
+       rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+       if (WARN_ON(rc))
+               return;
+}
+
+void __init socfpga_gate_init(struct device_node *node)
+{
+       __socfpga_gate_init(node, &gateclk_ops);
+}