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Subject[RFC 09/50] ARM: at91: add PMC usb clock support using common clk framework.
Date
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@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(+)

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index a4d442d..ce4851d 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..008372e
--- /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@overkiz.com>
+ *
+ * This usbram 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 = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ 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 18c89c2..8a88b38 100644
--- a/include/linux/clk/at91.h
+++ b/include/linux/clk/at91.h
@@ -289,4 +289,13 @@ 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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