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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/sh/clk/cpg.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/sh/clk/cpg.c')
-rw-r--r--kernel/drivers/sh/clk/cpg.c492
1 files changed, 492 insertions, 0 deletions
diff --git a/kernel/drivers/sh/clk/cpg.c b/kernel/drivers/sh/clk/cpg.c
new file mode 100644
index 000000000..7442bc130
--- /dev/null
+++ b/kernel/drivers/sh/clk/cpg.c
@@ -0,0 +1,492 @@
+/*
+ * Helper routines for SuperH Clock Pulse Generator blocks (CPG).
+ *
+ * Copyright (C) 2010 Magnus Damm
+ * Copyright (C) 2010 - 2012 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/clk.h>
+#include <linux/compiler.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/sh_clk.h>
+
+#define CPG_CKSTP_BIT BIT(8)
+
+static unsigned int sh_clk_read(struct clk *clk)
+{
+ if (clk->flags & CLK_ENABLE_REG_8BIT)
+ return ioread8(clk->mapped_reg);
+ else if (clk->flags & CLK_ENABLE_REG_16BIT)
+ return ioread16(clk->mapped_reg);
+
+ return ioread32(clk->mapped_reg);
+}
+
+static void sh_clk_write(int value, struct clk *clk)
+{
+ if (clk->flags & CLK_ENABLE_REG_8BIT)
+ iowrite8(value, clk->mapped_reg);
+ else if (clk->flags & CLK_ENABLE_REG_16BIT)
+ iowrite16(value, clk->mapped_reg);
+ else
+ iowrite32(value, clk->mapped_reg);
+}
+
+static unsigned int r8(const void __iomem *addr)
+{
+ return ioread8(addr);
+}
+
+static unsigned int r16(const void __iomem *addr)
+{
+ return ioread16(addr);
+}
+
+static unsigned int r32(const void __iomem *addr)
+{
+ return ioread32(addr);
+}
+
+static int sh_clk_mstp_enable(struct clk *clk)
+{
+ sh_clk_write(sh_clk_read(clk) & ~(1 << clk->enable_bit), clk);
+ if (clk->status_reg) {
+ unsigned int (*read)(const void __iomem *addr);
+ int i;
+ void __iomem *mapped_status = (phys_addr_t)clk->status_reg -
+ (phys_addr_t)clk->enable_reg + clk->mapped_reg;
+
+ if (clk->flags & CLK_ENABLE_REG_8BIT)
+ read = r8;
+ else if (clk->flags & CLK_ENABLE_REG_16BIT)
+ read = r16;
+ else
+ read = r32;
+
+ for (i = 1000;
+ (read(mapped_status) & (1 << clk->enable_bit)) && i;
+ i--)
+ cpu_relax();
+ if (!i) {
+ pr_err("cpg: failed to enable %p[%d]\n",
+ clk->enable_reg, clk->enable_bit);
+ return -ETIMEDOUT;
+ }
+ }
+ return 0;
+}
+
+static void sh_clk_mstp_disable(struct clk *clk)
+{
+ sh_clk_write(sh_clk_read(clk) | (1 << clk->enable_bit), clk);
+}
+
+static struct sh_clk_ops sh_clk_mstp_clk_ops = {
+ .enable = sh_clk_mstp_enable,
+ .disable = sh_clk_mstp_disable,
+ .recalc = followparent_recalc,
+};
+
+int __init sh_clk_mstp_register(struct clk *clks, int nr)
+{
+ struct clk *clkp;
+ int ret = 0;
+ int k;
+
+ for (k = 0; !ret && (k < nr); k++) {
+ clkp = clks + k;
+ clkp->ops = &sh_clk_mstp_clk_ops;
+ ret |= clk_register(clkp);
+ }
+
+ return ret;
+}
+
+/*
+ * Div/mult table lookup helpers
+ */
+static inline struct clk_div_table *clk_to_div_table(struct clk *clk)
+{
+ return clk->priv;
+}
+
+static inline struct clk_div_mult_table *clk_to_div_mult_table(struct clk *clk)
+{
+ return clk_to_div_table(clk)->div_mult_table;
+}
+
+/*
+ * Common div ops
+ */
+static long sh_clk_div_round_rate(struct clk *clk, unsigned long rate)
+{
+ return clk_rate_table_round(clk, clk->freq_table, rate);
+}
+
+static unsigned long sh_clk_div_recalc(struct clk *clk)
+{
+ struct clk_div_mult_table *table = clk_to_div_mult_table(clk);
+ unsigned int idx;
+
+ clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
+ table, clk->arch_flags ? &clk->arch_flags : NULL);
+
+ idx = (sh_clk_read(clk) >> clk->enable_bit) & clk->div_mask;
+
+ return clk->freq_table[idx].frequency;
+}
+
+static int sh_clk_div_set_rate(struct clk *clk, unsigned long rate)
+{
+ struct clk_div_table *dt = clk_to_div_table(clk);
+ unsigned long value;
+ int idx;
+
+ idx = clk_rate_table_find(clk, clk->freq_table, rate);
+ if (idx < 0)
+ return idx;
+
+ value = sh_clk_read(clk);
+ value &= ~(clk->div_mask << clk->enable_bit);
+ value |= (idx << clk->enable_bit);
+ sh_clk_write(value, clk);
+
+ /* XXX: Should use a post-change notifier */
+ if (dt->kick)
+ dt->kick(clk);
+
+ return 0;
+}
+
+static int sh_clk_div_enable(struct clk *clk)
+{
+ if (clk->div_mask == SH_CLK_DIV6_MSK) {
+ int ret = sh_clk_div_set_rate(clk, clk->rate);
+ if (ret < 0)
+ return ret;
+ }
+
+ sh_clk_write(sh_clk_read(clk) & ~CPG_CKSTP_BIT, clk);
+ return 0;
+}
+
+static void sh_clk_div_disable(struct clk *clk)
+{
+ unsigned int val;
+
+ val = sh_clk_read(clk);
+ val |= CPG_CKSTP_BIT;
+
+ /*
+ * div6 clocks require the divisor field to be non-zero or the
+ * above CKSTP toggle silently fails. Ensure that the divisor
+ * array is reset to its initial state on disable.
+ */
+ if (clk->flags & CLK_MASK_DIV_ON_DISABLE)
+ val |= clk->div_mask;
+
+ sh_clk_write(val, clk);
+}
+
+static struct sh_clk_ops sh_clk_div_clk_ops = {
+ .recalc = sh_clk_div_recalc,
+ .set_rate = sh_clk_div_set_rate,
+ .round_rate = sh_clk_div_round_rate,
+};
+
+static struct sh_clk_ops sh_clk_div_enable_clk_ops = {
+ .recalc = sh_clk_div_recalc,
+ .set_rate = sh_clk_div_set_rate,
+ .round_rate = sh_clk_div_round_rate,
+ .enable = sh_clk_div_enable,
+ .disable = sh_clk_div_disable,
+};
+
+static int __init sh_clk_init_parent(struct clk *clk)
+{
+ u32 val;
+
+ if (clk->parent)
+ return 0;
+
+ if (!clk->parent_table || !clk->parent_num)
+ return 0;
+
+ if (!clk->src_width) {
+ pr_err("sh_clk_init_parent: cannot select parent clock\n");
+ return -EINVAL;
+ }
+
+ val = (sh_clk_read(clk) >> clk->src_shift);
+ val &= (1 << clk->src_width) - 1;
+
+ if (val >= clk->parent_num) {
+ pr_err("sh_clk_init_parent: parent table size failed\n");
+ return -EINVAL;
+ }
+
+ clk_reparent(clk, clk->parent_table[val]);
+ if (!clk->parent) {
+ pr_err("sh_clk_init_parent: unable to set parent");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init sh_clk_div_register_ops(struct clk *clks, int nr,
+ struct clk_div_table *table, struct sh_clk_ops *ops)
+{
+ struct clk *clkp;
+ void *freq_table;
+ int nr_divs = table->div_mult_table->nr_divisors;
+ int freq_table_size = sizeof(struct cpufreq_frequency_table);
+ int ret = 0;
+ int k;
+
+ freq_table_size *= (nr_divs + 1);
+ freq_table = kzalloc(freq_table_size * nr, GFP_KERNEL);
+ if (!freq_table) {
+ pr_err("%s: unable to alloc memory\n", __func__);
+ return -ENOMEM;
+ }
+
+ for (k = 0; !ret && (k < nr); k++) {
+ clkp = clks + k;
+
+ clkp->ops = ops;
+ clkp->priv = table;
+
+ clkp->freq_table = freq_table + (k * freq_table_size);
+ clkp->freq_table[nr_divs].frequency = CPUFREQ_TABLE_END;
+
+ ret = clk_register(clkp);
+ if (ret == 0)
+ ret = sh_clk_init_parent(clkp);
+ }
+
+ return ret;
+}
+
+/*
+ * div6 support
+ */
+static int sh_clk_div6_divisors[64] = {
+ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
+ 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
+ 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
+ 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64
+};
+
+static struct clk_div_mult_table div6_div_mult_table = {
+ .divisors = sh_clk_div6_divisors,
+ .nr_divisors = ARRAY_SIZE(sh_clk_div6_divisors),
+};
+
+static struct clk_div_table sh_clk_div6_table = {
+ .div_mult_table = &div6_div_mult_table,
+};
+
+static int sh_clk_div6_set_parent(struct clk *clk, struct clk *parent)
+{
+ struct clk_div_mult_table *table = clk_to_div_mult_table(clk);
+ u32 value;
+ int ret, i;
+
+ if (!clk->parent_table || !clk->parent_num)
+ return -EINVAL;
+
+ /* Search the parent */
+ for (i = 0; i < clk->parent_num; i++)
+ if (clk->parent_table[i] == parent)
+ break;
+
+ if (i == clk->parent_num)
+ return -ENODEV;
+
+ ret = clk_reparent(clk, parent);
+ if (ret < 0)
+ return ret;
+
+ value = sh_clk_read(clk) &
+ ~(((1 << clk->src_width) - 1) << clk->src_shift);
+
+ sh_clk_write(value | (i << clk->src_shift), clk);
+
+ /* Rebuild the frequency table */
+ clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
+ table, NULL);
+
+ return 0;
+}
+
+static struct sh_clk_ops sh_clk_div6_reparent_clk_ops = {
+ .recalc = sh_clk_div_recalc,
+ .round_rate = sh_clk_div_round_rate,
+ .set_rate = sh_clk_div_set_rate,
+ .enable = sh_clk_div_enable,
+ .disable = sh_clk_div_disable,
+ .set_parent = sh_clk_div6_set_parent,
+};
+
+int __init sh_clk_div6_register(struct clk *clks, int nr)
+{
+ return sh_clk_div_register_ops(clks, nr, &sh_clk_div6_table,
+ &sh_clk_div_enable_clk_ops);
+}
+
+int __init sh_clk_div6_reparent_register(struct clk *clks, int nr)
+{
+ return sh_clk_div_register_ops(clks, nr, &sh_clk_div6_table,
+ &sh_clk_div6_reparent_clk_ops);
+}
+
+/*
+ * div4 support
+ */
+static int sh_clk_div4_set_parent(struct clk *clk, struct clk *parent)
+{
+ struct clk_div_mult_table *table = clk_to_div_mult_table(clk);
+ u32 value;
+ int ret;
+
+ /* we really need a better way to determine parent index, but for
+ * now assume internal parent comes with CLK_ENABLE_ON_INIT set,
+ * no CLK_ENABLE_ON_INIT means external clock...
+ */
+
+ if (parent->flags & CLK_ENABLE_ON_INIT)
+ value = sh_clk_read(clk) & ~(1 << 7);
+ else
+ value = sh_clk_read(clk) | (1 << 7);
+
+ ret = clk_reparent(clk, parent);
+ if (ret < 0)
+ return ret;
+
+ sh_clk_write(value, clk);
+
+ /* Rebiuld the frequency table */
+ clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
+ table, &clk->arch_flags);
+
+ return 0;
+}
+
+static struct sh_clk_ops sh_clk_div4_reparent_clk_ops = {
+ .recalc = sh_clk_div_recalc,
+ .set_rate = sh_clk_div_set_rate,
+ .round_rate = sh_clk_div_round_rate,
+ .enable = sh_clk_div_enable,
+ .disable = sh_clk_div_disable,
+ .set_parent = sh_clk_div4_set_parent,
+};
+
+int __init sh_clk_div4_register(struct clk *clks, int nr,
+ struct clk_div4_table *table)
+{
+ return sh_clk_div_register_ops(clks, nr, table, &sh_clk_div_clk_ops);
+}
+
+int __init sh_clk_div4_enable_register(struct clk *clks, int nr,
+ struct clk_div4_table *table)
+{
+ return sh_clk_div_register_ops(clks, nr, table,
+ &sh_clk_div_enable_clk_ops);
+}
+
+int __init sh_clk_div4_reparent_register(struct clk *clks, int nr,
+ struct clk_div4_table *table)
+{
+ return sh_clk_div_register_ops(clks, nr, table,
+ &sh_clk_div4_reparent_clk_ops);
+}
+
+/* FSI-DIV */
+static unsigned long fsidiv_recalc(struct clk *clk)
+{
+ u32 value;
+
+ value = __raw_readl(clk->mapping->base);
+
+ value >>= 16;
+ if (value < 2)
+ return clk->parent->rate;
+
+ return clk->parent->rate / value;
+}
+
+static long fsidiv_round_rate(struct clk *clk, unsigned long rate)
+{
+ return clk_rate_div_range_round(clk, 1, 0xffff, rate);
+}
+
+static void fsidiv_disable(struct clk *clk)
+{
+ __raw_writel(0, clk->mapping->base);
+}
+
+static int fsidiv_enable(struct clk *clk)
+{
+ u32 value;
+
+ value = __raw_readl(clk->mapping->base) >> 16;
+ if (value < 2)
+ return 0;
+
+ __raw_writel((value << 16) | 0x3, clk->mapping->base);
+
+ return 0;
+}
+
+static int fsidiv_set_rate(struct clk *clk, unsigned long rate)
+{
+ int idx;
+
+ idx = (clk->parent->rate / rate) & 0xffff;
+ if (idx < 2)
+ __raw_writel(0, clk->mapping->base);
+ else
+ __raw_writel(idx << 16, clk->mapping->base);
+
+ return 0;
+}
+
+static struct sh_clk_ops fsidiv_clk_ops = {
+ .recalc = fsidiv_recalc,
+ .round_rate = fsidiv_round_rate,
+ .set_rate = fsidiv_set_rate,
+ .enable = fsidiv_enable,
+ .disable = fsidiv_disable,
+};
+
+int __init sh_clk_fsidiv_register(struct clk *clks, int nr)
+{
+ struct clk_mapping *map;
+ int i;
+
+ for (i = 0; i < nr; i++) {
+
+ map = kzalloc(sizeof(struct clk_mapping), GFP_KERNEL);
+ if (!map) {
+ pr_err("%s: unable to alloc memory\n", __func__);
+ return -ENOMEM;
+ }
+
+ /* clks[i].enable_reg came from SH_CLK_FSIDIV() */
+ map->phys = (phys_addr_t)clks[i].enable_reg;
+ map->len = 8;
+
+ clks[i].enable_reg = 0; /* remove .enable_reg */
+ clks[i].ops = &fsidiv_clk_ops;
+ clks[i].mapping = map;
+
+ clk_register(&clks[i]);
+ }
+
+ return 0;
+}