[PATCH v2 09/42] ARM: at91: add PMC usb clock
Boris BREZILLON
b.brezillon at overkiz.com
Wed Jul 17 09:52:18 EDT 2013
This is the at91 usb clock implementation using common clk framework.
This clock is used to clock usb ports (ohci, ehci and udc).
Signed-off-by: Boris BREZILLON <b.brezillon at overkiz.com>
---
arch/arm/mach-at91/Kconfig | 11 ++
drivers/clk/at91/Makefile | 1 +
drivers/clk/at91/clk-usb.c | 303 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/clk/at91.h | 9 ++
4 files changed, 324 insertions(+)
create mode 100644 drivers/clk/at91/clk-usb.c
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 1a24a1f..ac18755 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -3,6 +3,9 @@ if ARCH_AT91
config HAVE_AT91_UTMI
bool
+config HAVE_AT91_USB_CLK
+ bool
+
config HAVE_AT91_DBGU0
bool
@@ -69,6 +72,7 @@ config SOC_SAMA5D3
select HAVE_FB_ATMEL
select HAVE_AT91_DBGU1
select HAVE_AT91_UTMI
+ select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's SAMA5D3 family SoC.
This support covers SAMA5D31, SAMA5D33, SAMA5D34, SAMA5D35.
@@ -82,11 +86,13 @@ config SOC_AT91RM9200
select HAVE_AT91_DBGU0
select MULTI_IRQ_HANDLER
select SPARSE_IRQ
+ select HAVE_AT91_USB_CLK
config SOC_AT91SAM9260
bool "AT91SAM9260, AT91SAM9XE or AT91SAM9G20"
select HAVE_AT91_DBGU0
select SOC_AT91SAM9
+ select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's AT91SAM9260, AT91SAM9XE
or AT91SAM9G20 SoC.
@@ -96,6 +102,7 @@ config SOC_AT91SAM9261
select HAVE_AT91_DBGU0
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's AT91SAM9261 or AT91SAM9G10 SoC.
@@ -104,6 +111,7 @@ config SOC_AT91SAM9263
select HAVE_AT91_DBGU1
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ select HAVE_AT91_USB_CLK
config SOC_AT91SAM9RL
bool "AT91SAM9RL"
@@ -118,6 +126,7 @@ config SOC_AT91SAM9G45
select HAVE_FB_ATMEL
select SOC_AT91SAM9
select HAVE_AT91_UTMI
+ select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's AT91SAM9G45 family SoC.
This support covers AT91SAM9G45, AT91SAM9G46, AT91SAM9M10 and AT91SAM9M11.
@@ -128,6 +137,7 @@ config SOC_AT91SAM9X5
select HAVE_FB_ATMEL
select SOC_AT91SAM9
select HAVE_AT91_UTMI
+ select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's AT91SAM9x5 family SoC.
This means that your SAM9 name finishes with a '5' (except if it is
@@ -140,6 +150,7 @@ config SOC_AT91SAM9N12
select HAVE_AT91_DBGU0
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ select HAVE_AT91_USB_CLK
help
Select this if you are using Atmel's AT91SAM9N12 SoC.
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 76d09f0..bbfd245 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -7,3 +7,4 @@ obj-y += clk-system.o clk-peripheral.o
obj-$(CONFIG_AT91_PROGRAMMABLE_CLOCKS) += clk-programmable.o
obj-$(CONFIG_HAVE_AT91_UTMI) += clk-utmi.o
+obj-$(CONFIG_HAVE_AT91_USB_CLK) += clk-usb.o
diff --git a/drivers/clk/at91/clk-usb.c b/drivers/clk/at91/clk-usb.c
new file mode 100644
index 0000000..4af0fe3
--- /dev/null
+++ b/drivers/clk/at91/clk-usb.c
@@ -0,0 +1,303 @@
+/*
+ * drivers/clk/at91/clk-usb.c
+ *
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon at overkiz.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.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#define USB_SOURCE_MAX 2
+
+#define to_at91sam9x5_clk_usb(hw) \
+ container_of(hw, struct at91sam9x5_clk_usb, hw)
+struct at91sam9x5_clk_usb {
+ struct clk_hw hw;
+ u8 usbs0_unused; /* sam9n12 uses usbs0 to disable usb clock */
+};
+
+#define to_at91rm9200_clk_usb(hw) \
+ container_of(hw, struct at91rm9200_clk_usb, hw)
+struct at91rm9200_clk_usb {
+ struct clk_hw hw;
+ u32 divisors[4];
+};
+
+static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 tmp;
+ u8 usbdiv;
+ tmp = at91_pmc_read(AT91_PMC_USB);
+ usbdiv = (tmp & AT91_PMC_OHCIUSBDIV) >> 8;
+ return parent_rate / (usbdiv + 1);
+}
+
+static long at91sam9x5_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ unsigned long div;
+ unsigned long bestrate;
+ unsigned long tmp;
+
+ if (rate >= *parent_rate)
+ return *parent_rate;
+
+ div = *parent_rate / rate;
+ if (div > 15)
+ return *parent_rate / 16;
+
+ bestrate = *parent_rate / div;
+ tmp = *parent_rate / (div + 1);
+ if (bestrate - rate > rate - tmp)
+ bestrate = tmp;
+
+ return bestrate;
+}
+
+static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)
+{
+ u32 tmp;
+ struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
+ if (usb->usbs0_unused)
+ index++;
+ if (index > 1)
+ return -EINVAL;
+ tmp = at91_pmc_read(AT91_PMC_USB) & ~AT91_PMC_USBS;
+ if (index)
+ tmp |= AT91_PMC_USBS;
+ at91_pmc_write(AT91_PMC_USB, tmp);
+ return 0;
+}
+
+static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw)
+{
+ struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
+ if (usb->usbs0_unused)
+ return 0;
+ return at91_pmc_read(AT91_PMC_USB) & AT91_PMC_USBS;
+}
+
+static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 tmp;
+ unsigned long div = parent_rate / rate;
+ if (parent_rate % rate || div < 1 || div > 16)
+ return -EINVAL;
+ tmp = at91_pmc_read(AT91_PMC_USB) & ~AT91_PMC_OHCIUSBDIV;
+ tmp |= (div - 1) << 8;
+ at91_pmc_write(AT91_PMC_USB, tmp);
+
+ return 0;
+}
+
+static const struct clk_ops at91sam9x5_usb_ops = {
+ .recalc_rate = at91sam9x5_clk_usb_recalc_rate,
+ .round_rate = at91sam9x5_clk_usb_round_rate,
+ .get_parent = at91sam9x5_clk_usb_get_parent,
+ .set_parent = at91sam9x5_clk_usb_set_parent,
+ .set_rate = at91sam9x5_clk_usb_set_rate,
+};
+
+struct clk * __init
+at91sam9x5_clk_register_usb(const char *name, const char **parent_names,
+ u8 num_parents, u8 usbs0_unused)
+{
+ struct at91sam9x5_clk_usb *usb;
+ struct clk *clk = NULL;
+ struct clk_init_data init;
+
+ usb = kzalloc(sizeof(*usb), GFP_KERNEL);
+ if (!usb)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &at91sam9x5_usb_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ usb->usbs0_unused = usbs0_unused;
+ usb->hw.init = &init;
+
+ clk = clk_register(NULL, &usb->hw);
+
+ if (IS_ERR(clk))
+ kfree(usb);
+
+ return clk;
+}
+
+static unsigned long at91rm9200_clk_usb_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
+ u32 tmp;
+ u8 usbdiv;
+ tmp = at91_pmc_read(AT91_CKGR_PLLBR);
+ usbdiv = (tmp & AT91_PMC_USBDIV) >> 28;
+ if (usb->divisors[usbdiv])
+ return parent_rate / usb->divisors[usbdiv];
+ return 0;
+}
+
+static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
+ unsigned long bestrate = 0;
+ int bestdiff = -1;
+ unsigned long tmprate;
+ int tmpdiff;
+ int i = 0;
+
+ for (i = 0; i < 4; i++) {
+ if (!usb->divisors[i])
+ continue;
+ tmprate = *parent_rate / usb->divisors[i];
+ if (tmprate < rate)
+ tmpdiff = rate - tmprate;
+ else
+ tmpdiff = tmprate - rate;
+
+ if (bestdiff < 0 || bestdiff > tmpdiff) {
+ bestrate = tmprate;
+ bestdiff = tmpdiff;
+ }
+
+ if (!bestdiff)
+ break;
+ }
+
+ return bestrate;
+}
+
+static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 tmp;
+ int i;
+ struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
+ unsigned long div = parent_rate / rate;
+ if (parent_rate % rate)
+ return -EINVAL;
+ for (i = 0; i < 4; i++) {
+ if (usb->divisors[i] == div) {
+ tmp = at91_pmc_read(AT91_CKGR_PLLBR) &
+ ~AT91_PMC_USBDIV;
+ tmp |= i << 8;
+ at91_pmc_write(AT91_PMC_USB, tmp);
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static const struct clk_ops at91rm9200_usb_ops = {
+ .recalc_rate = at91rm9200_clk_usb_recalc_rate,
+ .round_rate = at91rm9200_clk_usb_round_rate,
+ .set_rate = at91rm9200_clk_usb_set_rate,
+};
+
+struct clk * __init
+at91rm9200_clk_register_usb(const char *name, const char *parent_name,
+ const u32 *divisors)
+{
+ struct at91rm9200_clk_usb *usb;
+ struct clk *clk = NULL;
+ struct clk_init_data init;
+
+ usb = kzalloc(sizeof(*usb), GFP_KERNEL);
+ if (!usb)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &at91rm9200_usb_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = 0;
+
+ usb->hw.init = &init;
+ memcpy(usb->divisors, divisors, sizeof(usb->divisors));
+
+ clk = clk_register(NULL, &usb->hw);
+
+ if (IS_ERR(clk))
+ kfree(usb);
+
+ return clk;
+}
+
+#if defined(CONFIG_OF)
+static void __init of_at91sam9x5_clk_usb_setup(struct device_node *np)
+{
+ struct clk *clk;
+ int i;
+ int num_parents;
+ u8 usbs0_unused;
+ const char *parent_names[USB_SOURCE_MAX];
+ const char *name = np->name;
+
+ num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ if (num_parents <= 0 || num_parents > USB_SOURCE_MAX)
+ return;
+
+ for (i = 0; i < num_parents; i++) {
+ parent_names[i] = of_clk_get_parent_name(np, i);
+ if (!parent_names[i])
+ return;
+ }
+
+ usbs0_unused = of_property_read_bool(np, "usbs0-unused");
+ of_property_read_string(np, "clock-output-names", &name);
+
+ clk = at91sam9x5_clk_register_usb(name, parent_names, num_parents,
+ usbs0_unused);
+
+ if (IS_ERR(clk))
+ return;
+
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(at91sam9x5_clk_usb, "atmel,at91sam9x5-clk-usb",
+ of_at91sam9x5_clk_usb_setup);
+
+static void __init of_at91rm9200_clk_usb_setup(struct device_node *np)
+{
+ struct clk *clk;
+ const char *parent_name;
+ const char *name = np->name;
+ u32 divisors[4] = {0, 0, 0, 0};
+
+ parent_name = of_clk_get_parent_name(np, 0);
+ if (!parent_name)
+ return;
+
+ of_property_read_u32_array(np, "divisors", divisors, 4);
+ if (!divisors[0])
+ return;
+
+ of_property_read_string(np, "clock-output-names", &name);
+
+ clk = at91rm9200_clk_register_usb(name, parent_name, divisors);
+
+ if (IS_ERR(clk))
+ return;
+
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(at91rm9200_clk_usb, "atmel,at91rm9200-clk-usb",
+ of_at91rm9200_clk_usb_setup);
+#endif
diff --git a/include/linux/clk/at91.h b/include/linux/clk/at91.h
index 47ef7e8..2d083d1 100644
--- a/include/linux/clk/at91.h
+++ b/include/linux/clk/at91.h
@@ -292,4 +292,13 @@ at91_clk_register_programmable(const char *name, const char **parent_names,
struct clk * __init
at91_clk_register_utmi(const char *name, const char *parent_name);
+
+struct clk * __init
+at91rm9200_clk_register_usb(const char *name, const char *parent_name,
+ const u32 *divisors);
+
+struct clk * __init
+at91sam9x5_clk_register_usb(const char *name, const char **parent_names,
+ u8 num_parents, u8 usbs0_unused);
+
#endif
--
1.7.9.5
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