[PATCH 2/8][Version 2] MPC5121 clock driver
John Rigby
jrigby at freescale.com
Wed Jun 25 07:24:26 EST 2008
Implements the api defined in include/clk.h
Current only getting frequencies is supported
not setting.
Signed-off-by: John Rigby <jrigby at freescale.com>
---
arch/powerpc/platforms/512x/Makefile | 1 +
arch/powerpc/platforms/512x/clock.c | 720 ++++++++++++++++++++++++++++++++++
2 files changed, 721 insertions(+), 0 deletions(-)
create mode 100644 arch/powerpc/platforms/512x/clock.c
diff --git a/arch/powerpc/platforms/512x/Makefile b/arch/powerpc/platforms/512x/Makefile
index 232c89f..ef6c925 100644
--- a/arch/powerpc/platforms/512x/Makefile
+++ b/arch/powerpc/platforms/512x/Makefile
@@ -1,4 +1,5 @@
#
# Makefile for the Freescale PowerPC 512x linux kernel.
#
+obj-y := clock.o
obj-$(CONFIG_MPC5121_ADS) += mpc5121_ads.o
diff --git a/arch/powerpc/platforms/512x/clock.c b/arch/powerpc/platforms/512x/clock.c
new file mode 100644
index 0000000..5e0cd4c
--- /dev/null
+++ b/arch/powerpc/platforms/512x/clock.c
@@ -0,0 +1,720 @@
+/*
+ * Copyright (C) 2007,2008 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author: John Rigby <jrigby at freescale.com>
+ *
+ * Implements the clk api defined in include/linux/clk.h
+ *
+ * Original based on linux/arch/arm/mach-integrator/clock.c
+ *
+ * Copyright (C) 2004 ARM Limited.
+ * Written by Deep Blue Solutions Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+
+#include <linux/of_platform.h>
+#include <asm/mpc512x.h>
+
+static int clocks_initialized;
+
+#define CLK_HAS_RATE 0x1 /* has rate in MHz */
+#define CLK_HAS_CTRL 0x2 /* has control reg and bit */
+
+struct clk {
+ struct list_head node;
+ char name[32];
+ int flags;
+ struct device *dev;
+ unsigned long rate;
+ struct module *owner;
+ void (*calc) (struct clk *);
+ struct clk *parent;
+ int reg, bit; /* CLK_HAS_CTRL */
+ int div_shift; /* only used by generic_div_clk_calc */
+};
+
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+ struct clk *p, *clk = ERR_PTR(-ENOENT);
+ int dev_match = 0;
+ int id_match = 0;
+
+ if (dev == NULL && id == NULL)
+ return NULL;
+
+ mutex_lock(&clocks_mutex);
+ list_for_each_entry(p, &clocks, node) {
+ if (dev && dev == p->dev)
+ dev_match++;
+ if (strcmp(id, p->name) == 0)
+ id_match++;
+ if ((dev_match || id_match) && try_module_get(p->owner)) {
+ clk = p;
+ break;
+ }
+ }
+ mutex_unlock(&clocks_mutex);
+
+ return clk;
+}
+EXPORT_SYMBOL(clk_get);
+
+#undef CLK_DEBUG
+#ifdef CLK_DEBUG
+void dump_clocks(void)
+{
+ struct clk *p;
+
+ mutex_lock(&clocks_mutex);
+ printk(KERN_INFO "CLOCKS:\n");
+ list_for_each_entry(p, &clocks, node) {
+ printk(KERN_INFO " %s %ld", p->name, p->rate);
+ if (p->parent)
+ printk(KERN_INFO " %s %ld", p->parent->name,
+ p->parent->rate);
+ if (p->flags & CLK_HAS_CTRL)
+ printk(KERN_INFO " reg/bit %d/%d", p->reg, p->bit);
+ printk("\n");
+ }
+ mutex_unlock(&clocks_mutex);
+}
+#define DEBUG_CLK_DUMP() dump_clocks()
+#else
+#define DEBUG_CLK_DUMP()
+#endif
+
+
+void clk_put(struct clk *clk)
+{
+ module_put(clk->owner);
+}
+EXPORT_SYMBOL(clk_put);
+
+#define NRPSC 12
+
+struct mpc512x_clockctl {
+ u32 spmr; /* System PLL Mode Reg */
+ u32 sccr[2]; /* System Clk Ctrl Reg 1 & 2 */
+ u32 scfr1; /* System Clk Freq Reg 1 */
+ u32 scfr2; /* System Clk Freq Reg 2 */
+ u32 reserved;
+ u32 bcr; /* Bread Crumb Reg */
+ u32 pccr[NRPSC]; /* PSC Clk Ctrl Reg 0-11 */
+ u32 spccr; /* SPDIF Clk Ctrl Reg */
+ u32 cccr; /* CFM Clk Ctrl Reg */
+ u32 dccr; /* DIU Clk Cnfg Reg */
+};
+
+struct mpc512x_clockctl __iomem *clockctl;
+
+int clk_enable(struct clk *clk)
+{
+ unsigned int mask;
+
+ if (clk->flags & CLK_HAS_CTRL) {
+ mask = in_be32(&clockctl->sccr[clk->reg]);
+ mask |= 1 << clk->bit;
+ out_be32(&clockctl->sccr[clk->reg], mask);
+ }
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+ unsigned int mask;
+
+ if (clk->flags & CLK_HAS_CTRL) {
+ mask = in_be32(&clockctl->sccr[clk->reg]);
+ mask &= ~(1 << clk->bit);
+ out_be32(&clockctl->sccr[clk->reg], mask);
+ }
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (clk->flags & CLK_HAS_RATE)
+ return clk->rate;
+ else
+ return 0;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ return rate;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+static int clk_register(struct clk *clk)
+{
+ mutex_lock(&clocks_mutex);
+ list_add(&clk->node, &clocks);
+ mutex_unlock(&clocks_mutex);
+ return 0;
+}
+
+static unsigned long spmf_mult(void)
+{
+ /*
+ * Convert spmf to multiplier
+ */
+ static int spmf_to_mult[] = {
+ 68, 1, 12, 16,
+ 20, 24, 28, 32,
+ 36, 40, 44, 48,
+ 52, 56, 60, 64
+ };
+ int spmf = (clockctl->spmr >> 24) & 0xf;
+ return spmf_to_mult[spmf];
+}
+
+static unsigned long sysdiv_div_x_2(void)
+{
+ /*
+ * Convert sysdiv to divisor x 2
+ * Some divisors have fractional parts so
+ * multiply by 2 then divide by this value
+ */
+ static int sysdiv_to_div_x_2[] = {
+ 4, 5, 6, 7,
+ 8, 9, 10, 14,
+ 12, 16, 18, 22,
+ 20, 24, 26, 30,
+ 28, 32, 34, 38,
+ 36, 40, 42, 46,
+ 44, 48, 50, 54,
+ 52, 56, 58, 62,
+ 60, 64, 66,
+ };
+ int sysdiv = (clockctl->scfr2 >> 26) & 0x3f;
+ return sysdiv_to_div_x_2[sysdiv];
+}
+
+static unsigned long ref_to_sys(unsigned long rate)
+{
+ rate *= spmf_mult();
+ rate *= 2;
+ rate /= sysdiv_div_x_2();
+
+ return rate;
+}
+
+static unsigned long sys_to_ref(unsigned long rate)
+{
+ rate *= sysdiv_div_x_2();
+ rate /= 2;
+ rate /= spmf_mult();
+
+ return rate;
+}
+
+static long ips_to_ref(unsigned long rate)
+{
+ int ips_div = (clockctl->scfr1 >> 23) & 0x7;
+
+ rate *= ips_div; /* csb_clk = ips_clk * ips_div */
+ rate *= 2; /* sys_clk = csb_clk * 2 */
+ return sys_to_ref(rate);
+}
+
+static unsigned long devtree_getfreq(char *clockname)
+{
+ struct device_node *np;
+ const unsigned int *prop;
+ unsigned int val = 0;
+
+ np = of_find_node_by_type(NULL, "soc");
+ if (np) {
+ prop = of_get_property(np, clockname, NULL);
+ if (prop)
+ val = *prop;
+ of_node_put(np);
+ }
+ return val;
+}
+
+static void ref_clk_calc(struct clk *clk)
+{
+ unsigned long rate;
+
+ rate = devtree_getfreq("bus-frequency");
+ if (rate == 0) {
+ printk(KERN_WARNING
+ "No bus-frequency in dev tree using 66MHz\n");
+ clk->rate = 66000000;
+ return;
+ }
+ clk->rate = ips_to_ref(rate);
+}
+
+static struct clk ref_clk = {
+ .name = "ref_clk",
+ .calc = ref_clk_calc,
+};
+
+
+static void sys_clk_calc(struct clk *clk)
+{
+ clk->rate = ref_to_sys(ref_clk.rate);
+}
+
+static struct clk sys_clk = {
+ .name = "sys_clk",
+ .calc = sys_clk_calc,
+};
+
+static void diu_clk_calc(struct clk *clk)
+{
+ int diudiv_x_2 = clockctl->scfr1 & 0xff;
+ unsigned long rate;
+
+ rate = sys_clk.rate;
+
+ rate *= 2;
+ rate /= diudiv_x_2;
+
+ clk->rate = rate;
+}
+
+static void half_clk_calc(struct clk *clk)
+{
+ clk->rate = clk->parent->rate / 2;
+}
+
+static void generic_div_clk_calc(struct clk *clk)
+{
+ int div = (clockctl->scfr1 >> clk->div_shift) & 0x7;
+
+ clk->rate = clk->parent->rate / div;
+}
+
+static void unity_clk_calc(struct clk *clk)
+{
+ clk->rate = clk->parent->rate;
+}
+
+static struct clk csb_clk = {
+ .name = "csb_clk",
+ .calc = half_clk_calc,
+ .parent = &sys_clk,
+};
+
+static void e300_clk_calc(struct clk *clk)
+{
+ int spmf = (clockctl->spmr >> 16) & 0xf;
+ int ratex2 = clk->parent->rate * spmf;
+
+ clk->rate = ratex2 / 2;
+}
+
+static struct clk e300_clk = {
+ .name = "e300_clk",
+ .calc = e300_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk ips_clk = {
+ .name = "ips_clk",
+ .calc = generic_div_clk_calc,
+ .parent = &csb_clk,
+ .div_shift = 23,
+};
+
+/*
+ * Clocks controlled by SCCR1 (.reg = 0)
+ */
+static struct clk lpc_clk = {
+ .name = "lpc_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 30,
+ .calc = generic_div_clk_calc,
+ .parent = &ips_clk,
+ .div_shift = 11,
+};
+
+static struct clk nfc_clk = {
+ .name = "nfc_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 29,
+ .calc = generic_div_clk_calc,
+ .parent = &ips_clk,
+ .div_shift = 8,
+};
+
+static struct clk pata_clk = {
+ .name = "pata_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 28,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+/*
+ * PSC clocks (bits 27 - 16)
+ * are setup elsewhere
+ */
+
+static struct clk sata_clk = {
+ .name = "sata_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 14,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+static struct clk fec_clk = {
+ .name = "fec_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 13,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+static struct clk pci_clk = {
+ .name = "pci_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 0,
+ .bit = 11,
+ .calc = generic_div_clk_calc,
+ .parent = &csb_clk,
+ .div_shift = 20,
+};
+
+/*
+ * Clocks controlled by SCCR2 (.reg = 1)
+ */
+static struct clk diu_clk = {
+ .name = "diu_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 31,
+ .calc = diu_clk_calc,
+};
+
+static struct clk axe_clk = {
+ .name = "axe_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 30,
+ .calc = unity_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk usb1_clk = {
+ .name = "usb1_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 28,
+ .calc = unity_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk usb2_clk = {
+ .name = "usb2_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 27,
+ .calc = unity_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk i2c_clk = {
+ .name = "i2c_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 26,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+static struct clk mscan_clk = {
+ .name = "mscan_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 25,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+static struct clk sdhc_clk = {
+ .name = "sdhc_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 24,
+ .calc = unity_clk_calc,
+ .parent = &ips_clk,
+};
+
+static struct clk mbx_bus_clk = {
+ .name = "mbx_bus_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 22,
+ .calc = half_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk mbx_clk = {
+ .name = "mbx_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 21,
+ .calc = unity_clk_calc,
+ .parent = &csb_clk,
+};
+
+static struct clk mbx_3d_clk = {
+ .name = "mbx_3d_clk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 20,
+ .calc = generic_div_clk_calc,
+ .parent = &mbx_bus_clk,
+ .div_shift = 14,
+};
+
+static void psc_mclk_in_calc(struct clk *clk)
+{
+ clk->rate = devtree_getfreq("psc_mclk_in");
+ if (!clk->rate)
+ clk->rate = 25000000;
+}
+
+static struct clk psc_mclk_in = {
+ .name = "psc_mclk_in",
+ .calc = psc_mclk_in_calc,
+};
+
+static struct clk spdif_txclk = {
+ .name = "spdif_txclk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 23,
+};
+
+static struct clk spdif_rxclk = {
+ .name = "spdif_rxclk",
+ .flags = CLK_HAS_CTRL,
+ .reg = 1,
+ .bit = 23,
+};
+
+static void ac97_clk_calc(struct clk *clk)
+{
+ /* ac97 bit clock is always 24.567 MHz */
+ clk->rate = 24567000;
+}
+
+static struct clk ac97_clk = {
+ .name = "ac97_clk_in",
+ .calc = ac97_clk_calc,
+};
+
+struct clk *rate_clks[] = {
+ &ref_clk,
+ &sys_clk,
+ &diu_clk,
+ &csb_clk,
+ &e300_clk,
+ &ips_clk,
+ &fec_clk,
+ &sata_clk,
+ &pata_clk,
+ &nfc_clk,
+ &lpc_clk,
+ &mbx_bus_clk,
+ &mbx_clk,
+ &mbx_3d_clk,
+ &axe_clk,
+ &usb1_clk,
+ &usb2_clk,
+ &i2c_clk,
+ &mscan_clk,
+ &sdhc_clk,
+ &pci_clk,
+ &psc_mclk_in,
+ &spdif_txclk,
+ &spdif_rxclk,
+ &ac97_clk,
+ NULL
+};
+
+static void rate_clk_init(struct clk *clk)
+{
+ if (clk->calc) {
+ clk->calc(clk);
+ clk->flags |= CLK_HAS_RATE;
+ clk_register(clk);
+ } else {
+ printk(KERN_WARNING
+ "Could not initialize clk %s without a calc routine\n",
+ clk->name);
+ }
+}
+
+static void rate_clks_init(void)
+{
+ struct clk **cpp, *clk;
+
+ cpp = rate_clks;
+ while ((clk = *cpp++))
+ rate_clk_init(clk);
+}
+
+/*
+ * There are two clk enable registers with 32 enable bits each
+ * psc clocks and device clocks are all stored in dev_clks
+ */
+struct clk dev_clks[2][32];
+
+/*
+ * Given a psc number return the dev_clk
+ * associated with it
+ */
+static struct clk *psc_dev_clk(int pscnum)
+{
+ int reg, bit;
+ struct clk *clk;
+
+ reg = 0;
+ bit = 27 - pscnum;
+
+ clk = &dev_clks[reg][bit];
+ clk->reg = 0;
+ clk->bit = bit;
+ return clk;
+}
+
+/*
+ * PSC clock rate calculation
+ */
+static void psc_calc_rate(struct clk *clk, int pscnum, struct device_node *np)
+{
+ unsigned long mclk_src = sys_clk.rate;
+ unsigned long mclk_div;
+
+ /*
+ * Can only change value of mclk divider
+ * when the divider is disabled.
+ *
+ * Zero is not a valid divider so minimum
+ * divider is 1
+ *
+ * disable/set divider/enable
+ */
+ out_be32(&clockctl->pccr[pscnum], 0);
+ out_be32(&clockctl->pccr[pscnum], 0x00020000);
+ out_be32(&clockctl->pccr[pscnum], 0x00030000);
+
+ if (clockctl->pccr[pscnum] & 0x80) {
+ clk->rate = spdif_rxclk.rate;
+ return;
+ }
+
+ switch ((clockctl->pccr[pscnum] >> 14) & 0x3) {
+ case 0:
+ mclk_src = sys_clk.rate;
+ break;
+ case 1:
+ mclk_src = ref_clk.rate;
+ break;
+ case 2:
+ mclk_src = psc_mclk_in.rate;
+ break;
+ case 3:
+ mclk_src = spdif_txclk.rate;
+ break;
+ }
+
+ mclk_div = ((clockctl->pccr[pscnum] >> 17) & 0x7fff) + 1;
+ clk->rate = mclk_src / mclk_div;
+}
+
+/*
+ * Find all psc nodes in device tree and assign a clock
+ * with name "psc%d_mclk" and dev pointing at the device
+ * returned from of_find_device_by_node
+ */
+static void psc_clks_init(void)
+{
+ struct device_node *np;
+ const u32 *cell_index;
+ struct of_device *ofdev;
+
+ for_each_compatible_node(np, NULL, "fsl,mpc5121-psc") {
+ cell_index = of_get_property(np, "cell-index", NULL);
+ if (cell_index) {
+ int pscnum = *cell_index;
+ struct clk *clk = psc_dev_clk(pscnum);
+
+ clk->flags = CLK_HAS_RATE | CLK_HAS_CTRL;
+ ofdev = of_find_device_by_node(np);
+ clk->dev = &ofdev->dev;
+ /*
+ * AC97 is special rate clock does
+ * not go through normal path
+ */
+ if (strcmp("ac97", np->name) == 0)
+ clk->rate = ac97_clk.rate;
+ else
+ psc_calc_rate(clk, pscnum, np);
+ sprintf(clk->name, "psc%d_mclk", pscnum);
+ clk_register(clk);
+ clk_enable(clk);
+ }
+ }
+}
+
+static int
+mpc5121_clk_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-clock");
+ clockctl = of_iomap(np, 0);
+ of_node_put(np);
+
+ if (!clockctl) {
+ printk(KERN_ERR "Could not map clock control registers\n");
+ return 0;
+ }
+
+ rate_clks_init();
+ psc_clks_init();
+
+ /* leave clockctl mapped forever */
+ /*iounmap(clockctl); */
+ DEBUG_CLK_DUMP();
+ clocks_initialized++;
+ return 0;
+}
+
+
+arch_initcall(mpc5121_clk_init);
--
1.5.6.rc0.46.gd2b3
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