summaryrefslogtreecommitdiffstats
path: root/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
diff options
context:
space:
mode:
authordmitry pervushin <dimka@nomadgs.com>2007-04-24 13:39:09 +0900
committerPaul Mundt <lethal@hera.kernel.org>2007-05-07 02:11:56 +0000
commit1929cb340b74904c130fdf3de3fe5bbedb68a5aa (patch)
tree2675de406fca78e6bfd5b29535bbb220a167bc2e /arch/sh/kernel/cpu/sh4a/clock-sh7722.c
parent34a780a0afeb8f99c9ca9934f4cc0822541769c6 (diff)
sh: SH7722 clock framework support.
This adds support for the SH7722 (MobileR) to the clock framework. Signed-off-by: dmitry pervushin <dimka@nomadgs.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel/cpu/sh4a/clock-sh7722.c')
-rw-r--r--arch/sh/kernel/cpu/sh4a/clock-sh7722.c600
1 files changed, 600 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/sh4a/clock-sh7722.c b/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
new file mode 100644
index 00000000000..29090035bc5
--- /dev/null
+++ b/arch/sh/kernel/cpu/sh4a/clock-sh7722.c
@@ -0,0 +1,600 @@
+/*
+ * arch/sh/kernel/cpu/sh4a/clock-sh7722.c
+ *
+ * SH7722 support for the clock framework
+ *
+ * Copyright (c) 2006-2007 Nomad Global Solutions Inc
+ * Based on code for sh7343 by 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/init.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <asm/clock.h>
+#include <asm/freq.h>
+
+#define SH7722_PLL_FREQ (32000000/8)
+#define N (-1)
+#define NM (-2)
+#define ROUND_NEAREST 0
+#define ROUND_DOWN -1
+#define ROUND_UP +1
+
+static int adjust_algos[][3] = {
+ {}, /* NO_CHANGE */
+ { NM, N, 1 }, /* N:1, N:1 */
+ { 3, 2, 2 }, /* 3:2:2 */
+ { 5, 2, 2 }, /* 5:2:2 */
+ { N, 1, 1 }, /* N:1:1 */
+
+ { N, 1 }, /* N:1 */
+
+ { N, 1 }, /* N:1 */
+ { 3, 2 },
+ { 4, 3 },
+ { 5, 4 },
+
+ { N, 1 }
+};
+
+static unsigned long adjust_pair_of_clocks(unsigned long r1, unsigned long r2,
+ int m1, int m2, int round_flag)
+{
+ unsigned long rem, div;
+ int the_one = 0;
+
+ pr_debug( "Actual values: r1 = %ld\n", r1);
+ pr_debug( "...............r2 = %ld\n", r2);
+
+ if (m1 == m2) {
+ r2 = r1;
+ pr_debug( "setting equal rates: r2 now %ld\n", r2);
+ } else if ((m2 == N && m1 == 1) ||
+ (m2 == NM && m1 == N)) { /* N:1 or NM:N */
+ pr_debug( "Setting rates as 1:N (N:N*M)\n");
+ rem = r2 % r1;
+ pr_debug( "...remainder = %ld\n", rem);
+ if (rem) {
+ div = r2 / r1;
+ pr_debug( "...div = %ld\n", div);
+ switch (round_flag) {
+ case ROUND_NEAREST:
+ the_one = rem >= r1/2 ? 1 : 0; break;
+ case ROUND_UP:
+ the_one = 1; break;
+ case ROUND_DOWN:
+ the_one = 0; break;
+ }
+
+ r2 = r1 * (div + the_one);
+ pr_debug( "...setting r2 to %ld\n", r2);
+ }
+ } else if ((m2 == 1 && m1 == N) ||
+ (m2 == N && m1 == NM)) { /* 1:N or N:NM */
+ pr_debug( "Setting rates as N:1 (N*M:N)\n");
+ rem = r1 % r2;
+ pr_debug( "...remainder = %ld\n", rem);
+ if (rem) {
+ div = r1 / r2;
+ pr_debug( "...div = %ld\n", div);
+ switch (round_flag) {
+ case ROUND_NEAREST:
+ the_one = rem > r2/2 ? 1 : 0; break;
+ case ROUND_UP:
+ the_one = 0; break;
+ case ROUND_DOWN:
+ the_one = 1; break;
+ }
+
+ r2 = r1 / (div + the_one);
+ pr_debug( "...setting r2 to %ld\n", r2);
+ }
+ } else { /* value:value */
+ pr_debug( "Setting rates as %d:%d\n", m1, m2);
+ div = r1 / m1;
+ r2 = div * m2;
+ pr_debug( "...div = %ld\n", div);
+ pr_debug( "...setting r2 to %ld\n", r2);
+ }
+
+ return r2;
+}
+
+static void adjust_clocks(int originate, int *l, unsigned long v[],
+ int n_in_line)
+{
+ int x;
+
+ pr_debug( "Go down from %d...\n", originate);
+ /* go up recalculation clocks */
+ for (x = originate; x>0; x -- )
+ v[x-1] = adjust_pair_of_clocks(v[x], v[x-1],
+ l[x], l[x-1],
+ ROUND_UP);
+
+ pr_debug( "Go up from %d...\n", originate);
+ /* go down recalculation clocks */
+ for (x = originate; x<n_in_line - 1; x ++ )
+ v[x+1] = adjust_pair_of_clocks(v[x], v[x+1],
+ l[x], l[x+1],
+ ROUND_UP);
+}
+
+
+/*
+ * SH7722 uses a common set of multipliers and divisors, so this
+ * is quite simple..
+ */
+
+/*
+ * Instead of having two separate multipliers/divisors set, like this:
+ *
+ * static int multipliers[] = { 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
+ * static int divisors[] = { 1, 3, 2, 5, 3, 4, 5, 6, 8, 10, 12, 16, 20 };
+ *
+ * I created the divisors2 array, which is used to calculate rate like
+ * rate = parent * 2 / divisors2[ divisor ];
+*/
+static int divisors2[] = { 2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40 };
+
+static void master_clk_init(struct clk *clk)
+{
+ clk_set_rate(clk, clk_get_rate(clk));
+}
+
+static void master_clk_recalc(struct clk *clk)
+{
+ unsigned long frqcr = ctrl_inl(FRQCR);
+
+ clk->rate = CONFIG_SH_PCLK_FREQ * (1 + (frqcr >> 24 & 0xF));
+}
+
+static int master_clk_setrate(struct clk *clk, unsigned long rate, int id)
+{
+ int div = rate / SH7722_PLL_FREQ;
+ int master_divs[] = { 2, 3, 4, 6, 8, 16 };
+ int index;
+ unsigned long frqcr;
+
+ if (rate < SH7722_PLL_FREQ * 2)
+ return -EINVAL;
+
+ for (index = 1; index < ARRAY_SIZE(master_divs); index++)
+ if (div >= master_divs[index - 1] && div < master_divs[index])
+ break;
+
+ if (index >= ARRAY_SIZE(master_divs))
+ index = ARRAY_SIZE(master_divs);
+ div = master_divs[index - 1];
+
+ frqcr = ctrl_inl(FRQCR);
+ frqcr &= ~(0xF << 24);
+ frqcr |= ( (div-1) << 24);
+ ctrl_outl(frqcr, FRQCR);
+
+ return 0;
+}
+
+static struct clk_ops sh7722_master_clk_ops = {
+ .init = master_clk_init,
+ .recalc = master_clk_recalc,
+ .set_rate = master_clk_setrate,
+};
+
+struct frqcr_context {
+ unsigned mask;
+ unsigned shift;
+};
+
+struct frqcr_context sh7722_get_clk_context(const char *name)
+{
+ struct frqcr_context ctx = { 0, };
+
+ if (!strcmp(name, "peripheral_clk")) {
+ ctx.shift = 0;
+ ctx.mask = 0xF;
+ } else if (!strcmp(name, "sdram_clk")) {
+ ctx.shift = 4;
+ ctx.mask = 0xF;
+ } else if (!strcmp(name, "bus_clk")) {
+ ctx.shift = 8;
+ ctx.mask = 0xF;
+ } else if (!strcmp(name, "sh_clk")) {
+ ctx.shift = 12;
+ ctx.mask = 0xF;
+ } else if (!strcmp(name, "umem_clk")) {
+ ctx.shift = 16;
+ ctx.mask = 0xF;
+ } else if (!strcmp(name, "cpu_clk")) {
+ ctx.shift = 20;
+ ctx.mask = 7;
+ }
+ return ctx;
+}
+
+/**
+ * sh7722_find_divisors - find divisor for setting rate
+ *
+ * All sh7722 clocks use the same set of multipliers/divisors. This function
+ * chooses correct divisor to set the rate of clock with parent clock that
+ * generates frequency of 'parent_rate'
+ *
+ * @parent_rate: rate of parent clock
+ * @rate: requested rate to be set
+ */
+static int sh7722_find_divisors(unsigned long parent_rate, unsigned rate)
+{
+ unsigned div2 = parent_rate * 2 / rate;
+ int index;
+
+ if (rate > parent_rate)
+ return -EINVAL;
+
+ for (index = 1; index < ARRAY_SIZE(divisors2); index++) {
+ if (div2 > divisors2[index] && div2 <= divisors2[index])
+ break;
+ }
+ if (index >= ARRAY_SIZE(divisors2))
+ index = ARRAY_SIZE(divisors2) - 1;
+ return divisors2[index];
+}
+
+static void sh7722_frqcr_recalc(struct clk *clk)
+{
+ struct frqcr_context ctx = sh7722_get_clk_context(clk->name);
+ unsigned long frqcr = ctrl_inl(FRQCR);
+ int index;
+
+ index = (frqcr >> ctx.shift) & ctx.mask;
+ clk->rate = clk->parent->rate * 2 / divisors2[index];
+}
+
+static int sh7722_frqcr_set_rate(struct clk *clk, unsigned long rate,
+ int algo_id)
+{
+ struct frqcr_context ctx = sh7722_get_clk_context(clk->name);
+ unsigned long parent_rate = clk->parent->rate;
+ int div;
+ unsigned long frqcr;
+ int err = 0;
+
+ /* pretty invalid */
+ if (parent_rate < rate)
+ return -EINVAL;
+
+ /* look for multiplier/divisor pair */
+ div = sh7722_find_divisors(parent_rate, rate);
+ if (div<0)
+ return div;
+
+ /* calculate new value of clock rate */
+ clk->rate = parent_rate * 2 / div;
+ frqcr = ctrl_inl(FRQCR);
+
+ /* FIXME: adjust as algo_id specifies */
+ if (algo_id != NO_CHANGE) {
+ int originator;
+ char *algo_group_1[] = { "cpu_clk", "umem_clk", "sh_clk" };
+ char *algo_group_2[] = { "sh_clk", "bus_clk" };
+ char *algo_group_3[] = { "sh_clk", "sdram_clk" };
+ char *algo_group_4[] = { "bus_clk", "peripheral_clk" };
+ char *algo_group_5[] = { "cpu_clk", "peripheral_clk" };
+ char **algo_current = NULL;
+ /* 3 is the maximum number of clocks in relation */
+ struct clk *ck[3];
+ unsigned long values[3]; /* the same comment as above */
+ int part_length = -1;
+ int i;
+
+ /*
+ * all the steps below only required if adjustion was
+ * requested
+ */
+ if (algo_id == IUS_N1_N1 ||
+ algo_id == IUS_322 ||
+ algo_id == IUS_522 ||
+ algo_id == IUS_N11) {
+ algo_current = algo_group_1;
+ part_length = 3;
+ }
+ if (algo_id == SB_N1) {
+ algo_current = algo_group_2;
+ part_length = 2;
+ }
+ if (algo_id == SB3_N1 ||
+ algo_id == SB3_32 ||
+ algo_id == SB3_43 ||
+ algo_id == SB3_54) {
+ algo_current = algo_group_3;
+ part_length = 2;
+ }
+ if (algo_id == BP_N1) {
+ algo_current = algo_group_4;
+ part_length = 2;
+ }
+ if (algo_id == IP_N1) {
+ algo_current = algo_group_5;
+ part_length = 2;
+ }
+ if (!algo_current)
+ goto incorrect_algo_id;
+
+ originator = -1;
+ for (i = 0; i < part_length; i ++ ) {
+ if (originator >= 0 && !strcmp(clk->name,
+ algo_current[i]))
+ originator = i;
+ ck[i] = clk_get(NULL, algo_current[i]);
+ values[i] = clk_get_rate(ck[i]);
+ }
+
+ if (originator >= 0)
+ adjust_clocks(originator, adjust_algos[algo_id],
+ values, part_length);
+
+ for (i = 0; i < part_length; i ++ ) {
+ struct frqcr_context part_ctx;
+ int part_div;
+
+ if (likely(!err)) {
+ part_div = sh7722_find_divisors(parent_rate,
+ rate);
+ if (part_div > 0) {
+ part_ctx = sh7722_get_clk_context(
+ ck[i]->name);
+ frqcr &= ~(part_ctx.mask <<
+ part_ctx.shift);
+ frqcr |= part_div << part_ctx.shift;
+ } else
+ err = part_div;
+ }
+
+ ck[i]->ops->recalc(ck[i]);
+ clk_put(ck[i]);
+ }
+ }
+
+ /* was there any error during recalculation ? If so, bail out.. */
+ if (unlikely(err!=0))
+ goto out_err;
+
+ /* clear FRQCR bits */
+ frqcr &= ~(ctx.mask << ctx.shift);
+ frqcr |= div << ctx.shift;
+
+ /* ...and perform actual change */
+ ctrl_outl(frqcr, FRQCR);
+ return 0;
+
+incorrect_algo_id:
+ return -EINVAL;
+out_err:
+ return err;
+}
+
+static struct clk_ops sh7722_frqcr_clk_ops = {
+ .recalc = sh7722_frqcr_recalc,
+ .set_rate = sh7722_frqcr_set_rate,
+};
+
+/*
+ * clock ops methods for SIU A/B and IrDA clock
+ *
+ */
+static int sh7722_siu_which(struct clk *clk)
+{
+ if (!strcmp(clk->name, "siu_a_clk"))
+ return 0;
+ if (!strcmp(clk->name, "siu_b_clk"))
+ return 1;
+ if (!strcmp(clk->name, "irda_clk"))
+ return 2;
+ return -EINVAL;
+}
+
+static unsigned long sh7722_siu_regs[] = {
+ [0] = SCLKACR,
+ [1] = SCLKBCR,
+ [2] = IrDACLKCR,
+};
+
+static int sh7722_siu_start_stop(struct clk *clk, int enable)
+{
+ int siu = sh7722_siu_which(clk);
+ unsigned long r;
+
+ if (siu < 0)
+ return siu;
+ BUG_ON(siu > 2);
+ r = ctrl_inl(sh7722_siu_regs[siu]);
+ if (enable)
+ ctrl_outl(r & ~(1 << 8), sh7722_siu_regs[siu]);
+ else
+ ctrl_outl(r | (1 << 8), sh7722_siu_regs[siu]);
+ return 0;
+}
+
+static void sh7722_siu_enable(struct clk *clk)
+{
+ sh7722_siu_start_stop(clk, 1);
+}
+
+static void sh7722_siu_disable(struct clk *clk)
+{
+ sh7722_siu_start_stop(clk, 0);
+}
+
+static void sh7722_video_enable(struct clk *clk)
+{
+ unsigned long r;
+
+ r = ctrl_inl(VCLKCR);
+ ctrl_outl( r & ~(1<<8), VCLKCR);
+}
+
+static void sh7722_video_disable(struct clk *clk)
+{
+ unsigned long r;
+
+ r = ctrl_inl(VCLKCR);
+ ctrl_outl( r | (1<<8), VCLKCR);
+}
+
+static int sh7722_video_set_rate(struct clk *clk, unsigned long rate,
+ int algo_id)
+{
+ unsigned long r;
+
+ r = ctrl_inl(VCLKCR);
+ r &= ~0x3F;
+ r |= ((clk->parent->rate / rate - 1) & 0x3F);
+ ctrl_outl(r, VCLKCR);
+ return 0;
+}
+
+static void sh7722_video_recalc(struct clk *clk)
+{
+ unsigned long r;
+
+ r = ctrl_inl(VCLKCR);
+ clk->rate = clk->parent->rate / ((r & 0x3F) + 1);
+}
+
+static int sh7722_siu_set_rate(struct clk *clk, unsigned long rate, int algo_id)
+{
+ int siu = sh7722_siu_which(clk);
+ unsigned long r;
+ int div;
+
+ if (siu < 0)
+ return siu;
+ BUG_ON(siu > 2);
+ r = ctrl_inl(sh7722_siu_regs[siu]);
+ div = sh7722_find_divisors(clk->parent->rate, rate);
+ if (div < 0)
+ return div;
+ r = (r & ~0xF) | div;
+ ctrl_outl(r, sh7722_siu_regs[siu]);
+ return 0;
+}
+
+static void sh7722_siu_recalc(struct clk *clk)
+{
+ int siu = sh7722_siu_which(clk);
+ unsigned long r;
+
+ if (siu < 0)
+ return /* siu */ ;
+ BUG_ON(siu > 1);
+ r = ctrl_inl(sh7722_siu_regs[siu]);
+ clk->rate = clk->parent->rate * 2 / divisors2[r & 0xF];
+}
+
+static struct clk_ops sh7722_siu_clk_ops = {
+ .recalc = sh7722_siu_recalc,
+ .set_rate = sh7722_siu_set_rate,
+ .enable = sh7722_siu_enable,
+ .disable = sh7722_siu_disable,
+};
+
+static struct clk_ops sh7722_video_clk_ops = {
+ .recalc = sh7722_video_recalc,
+ .set_rate = sh7722_video_set_rate,
+ .enable = sh7722_video_enable,
+ .disable = sh7722_video_disable,
+};
+/*
+ * and at last, clock definitions themselves
+ */
+static struct clk sh7722_umem_clock = {
+ .name = "umem_clk",
+ .ops = &sh7722_frqcr_clk_ops,
+};
+
+static struct clk sh7722_sh_clock = {
+ .name = "sh_clk",
+ .ops = &sh7722_frqcr_clk_ops,
+};
+
+static struct clk sh7722_peripheral_clock = {
+ .name = "peripheral_clk",
+ .ops = &sh7722_frqcr_clk_ops,
+};
+
+static struct clk sh7722_sdram_clock = {
+ .name = "sdram_clk",
+ .ops = &sh7722_frqcr_clk_ops,
+};
+
+/*
+ * these three clocks - SIU A, SIU B, IrDA - share the same clk_ops
+ * methods of clk_ops determine which register they should access by
+ * examining clk->name field
+ */
+static struct clk sh7722_siu_a_clock = {
+ .name = "siu_a_clk",
+ .ops = &sh7722_siu_clk_ops,
+};
+
+static struct clk sh7722_siu_b_clock = {
+ .name = "siu_b_clk",
+ .ops = &sh7722_siu_clk_ops,
+};
+
+static struct clk sh7722_irda_clock = {
+ .name = "irda_clk",
+ .ops = &sh7722_siu_clk_ops,
+};
+
+static struct clk sh7722_video_clock = {
+ .name = "video_clk",
+ .ops = &sh7722_video_clk_ops,
+};
+
+static struct clk *sh7722_clocks[] = {
+ &sh7722_umem_clock,
+ &sh7722_sh_clock,
+ &sh7722_peripheral_clock,
+ &sh7722_sdram_clock,
+ &sh7722_siu_a_clock,
+ &sh7722_siu_b_clock,
+ &sh7722_irda_clock,
+ &sh7722_video_clock,
+};
+
+/*
+ * init in order: master, module, bus, cpu
+ */
+struct clk_ops *onchip_ops[] = {
+ &sh7722_master_clk_ops,
+ &sh7722_frqcr_clk_ops,
+ &sh7722_frqcr_clk_ops,
+ &sh7722_frqcr_clk_ops,
+};
+
+void __init
+arch_init_clk_ops(struct clk_ops **ops, int type)
+{
+ BUG_ON(type < 0 || type > ARRAY_SIZE(onchip_ops));
+ *ops = onchip_ops[type];
+}
+
+int __init sh7722_clock_init(void)
+{
+ struct clk *master;
+ int i;
+
+ master = clk_get(NULL, "master_clk");
+ for (i = 0; i < ARRAY_SIZE(sh7722_clocks); i++) {
+ pr_debug( "Registering clock '%s'\n", sh7722_clocks[i]->name);
+ sh7722_clocks[i]->parent = master;
+ clk_register(sh7722_clocks[i]);
+ }
+ clk_put(master);
+ return 0;
+}
+arch_initcall(sh7722_clock_init);