[PATCHv3 3/3] ARM: socfpga: Upgrade clk driver for socfpga to make use of dts clock entries
dinguyen at altera.com
dinguyen at altera.com
Thu Apr 11 11:55:26 EDT 2013
From: Dinh Nguyen <dinguyen at altera.com>
With this patch, the socfpga clk driver is able to query the clock and clock
rates appropriately.
Signed-off-by: Dinh Nguyen <dinguyen at altera.com>
---
arch/arm/mach-socfpga/socfpga.c | 6 ++
drivers/clk/socfpga/clk.c | 163 ++++++++++++++++++++++++++++++++++-----
2 files changed, 148 insertions(+), 21 deletions(-)
diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c
index 2cae16c..46a0513 100644
--- a/arch/arm/mach-socfpga/socfpga.c
+++ b/arch/arm/mach-socfpga/socfpga.c
@@ -15,6 +15,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/dw_apb_timer.h>
+#include <linux/clk-provider.h>
#include <linux/irqchip.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -29,6 +30,7 @@
void __iomem *socfpga_scu_base_addr = ((void __iomem *)(SOCFPGA_SCU_VIRT_BASE));
void __iomem *sys_manager_base_addr;
void __iomem *rst_manager_base_addr;
+void __iomem *clk_mgr_base_addr;
unsigned long cpu1start_addr;
static struct map_desc scu_io_desc __initdata = {
@@ -77,6 +79,9 @@ void __init socfpga_sysmgr_init(void)
np = of_find_compatible_node(NULL, NULL, "altr,rst-mgr");
rst_manager_base_addr = of_iomap(np, 0);
+
+ np = of_find_compatible_node(NULL, NULL, "altr,clk-mgr");
+ clk_mgr_base_addr = of_iomap(np, 0);
}
static void __init socfpga_init_irq(void)
@@ -102,6 +107,7 @@ static void __init socfpga_cyclone5_init(void)
{
l2x0_of_init(0, ~0UL);
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+ of_clk_init(NULL);
socfpga_init_clocks();
}
diff --git a/drivers/clk/socfpga/clk.c b/drivers/clk/socfpga/clk.c
index 2c855a6..bd11315 100644
--- a/drivers/clk/socfpga/clk.c
+++ b/drivers/clk/socfpga/clk.c
@@ -1,5 +1,6 @@
/*
- * Copyright (C) 2012 Altera Corporation <www.altera.com>
+ * Copyright 2011-2012 Calxeda, Inc.
+ * Copyright (C) 2012-2013 Altera Corporation <www.altera.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
@@ -11,41 +12,161 @@
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
+ * Based from clk-highbank.c
+ *
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
-#define SOCFPGA_OSC1_CLK 10000000
-#define SOCFPGA_MPU_CLK 800000000
-#define SOCFPGA_MAIN_QSPI_CLK 432000000
-#define SOCFPGA_MAIN_NAND_SDMMC_CLK 250000000
-#define SOCFPGA_S2F_USR_CLK 125000000
+/* Clock Manager offsets */
+#define CLKMGR_CTRL 0x0
+#define CLKMGR_BYPASS 0x4
-void __init socfpga_init_clocks(void)
+/* Clock bypass bits */
+#define MAINPLL_BYPASS (1<<0)
+#define SDRAMPLL_BYPASS (1<<1)
+#define SDRAMPLL_SRC_BYPASS (1<<2)
+#define PERPLL_BYPASS (1<<3)
+#define PERPLL_SRC_BYPASS (1<<4)
+
+#define SOCFPGA_PLL_BG_PWRDWN 0
+#define SOCFPGA_PLL_EXT_ENA 1
+#define SOCFPGA_PLL_PWR_DOWN 2
+#define SOCFPGA_PLL_DIVF_MASK 0x0000FFF8
+#define SOCFPGA_PLL_DIVF_SHIFT 3
+#define SOCFPGA_PLL_DIVQ_MASK 0x003F0000
+#define SOCFPGA_PLL_DIVQ_SHIFT 16
+
+extern void __iomem *clk_mgr_base_addr;
+
+struct socfpga_clk {
+ struct clk_gate hw;
+ char *parent_name;
+ char *clk_name;
+ u32 fixed_div;
+};
+#define to_socfpga_clk(p) container_of(p, struct socfpga_clk, hw.hw)
+
+static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
{
+ struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk);
+ unsigned long divf, divq, vco_freq, reg;
+ unsigned long bypass;
+
+ reg = readl(socfpgaclk->hw.reg);
+ bypass = readl(clk_mgr_base_addr + CLKMGR_BYPASS);
+ if (bypass & MAINPLL_BYPASS)
+ return parent_rate;
+
+ divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT;
+ divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT;
+ vco_freq = parent_rate * (divf + 1);
+ return vco_freq / (1 + divq);
+}
+
+
+static struct clk_ops clk_pll_ops = {
+ .recalc_rate = clk_pll_recalc_rate,
+};
+
+static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk);
+ u32 div;
+
+ if (socfpgaclk->fixed_div)
+ div = socfpgaclk->fixed_div;
+ else
+ div = ((readl(socfpgaclk->hw.reg) & 0x1ff) + 1);
+
+ return parent_rate / div;
+}
+
+static const struct clk_ops periclk_ops = {
+ .recalc_rate = clk_periclk_recalc_rate,
+};
+
+static __init struct clk *socfpga_clk_init(struct device_node *node,
+ const struct clk_ops *ops)
+{
+ u32 reg;
struct clk *clk;
+ struct socfpga_clk *socfpga_clk;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ struct clk_init_data init;
+ int rc;
+ u32 fixed_div;
+
+ rc = of_property_read_u32(node, "reg", ®);
+ if (WARN_ON(rc))
+ return NULL;
+
+ socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
+ if (WARN_ON(!socfpga_clk))
+ return NULL;
+
+ socfpga_clk->hw.reg = clk_mgr_base_addr + reg;
+
+ rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
+ if (rc)
+ socfpga_clk->fixed_div = 0;
+ else
+ socfpga_clk->fixed_div = fixed_div;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ init.flags = 0;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
- clk = clk_register_fixed_rate(NULL, "osc1_clk", NULL, CLK_IS_ROOT, SOCFPGA_OSC1_CLK);
- clk_register_clkdev(clk, "osc1_clk", NULL);
+ socfpga_clk->hw.hw.init = &init;
- clk = clk_register_fixed_rate(NULL, "mpu_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK);
- clk_register_clkdev(clk, "mpu_clk", NULL);
+ if (strcmp(clk_name, "main_pll") || strcmp(clk_name, "periph_pll") ||
+ strcmp(clk_name, "sdram_pll")) {
+ socfpga_clk->hw.bit_idx = SOCFPGA_PLL_EXT_ENA;
+ clk_pll_ops.enable = clk_gate_ops.enable;
+ clk_pll_ops.disable = clk_gate_ops.disable;
+ }
- clk = clk_register_fixed_rate(NULL, "main_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK/2);
- clk_register_clkdev(clk, "main_clk", NULL);
+ clk = clk_register(NULL, &socfpga_clk->hw.hw);
+ if (WARN_ON(IS_ERR(clk))) {
+ kfree(socfpga_clk);
+ return NULL;
+ }
+ rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ return clk;
+}
- clk = clk_register_fixed_rate(NULL, "dbg_base_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK/2);
- clk_register_clkdev(clk, "dbg_base_clk", NULL);
+static void __init socfpga_pll_init(struct device_node *node)
+{
+ socfpga_clk_init(node, &clk_pll_ops);
+}
+CLK_OF_DECLARE(socfpga_pll, "altr,socfpga-pll-clock", socfpga_pll_init);
- clk = clk_register_fixed_rate(NULL, "main_qspi_clk", NULL, CLK_IS_ROOT, SOCFPGA_MAIN_QSPI_CLK);
- clk_register_clkdev(clk, "main_qspi_clk", NULL);
+static void __init socfpga_periph_init(struct device_node *node)
+{
+ socfpga_clk_init(node, &periclk_ops);
+}
+CLK_OF_DECLARE(socfpga_periph, "altr,socfpga-perip-clk", socfpga_periph_init);
- clk = clk_register_fixed_rate(NULL, "main_nand_sdmmc_clk", NULL, CLK_IS_ROOT, SOCFPGA_MAIN_NAND_SDMMC_CLK);
- clk_register_clkdev(clk, "main_nand_sdmmc_clk", NULL);
+void __init socfpga_init_clocks(void)
+{
+ struct clk *clk;
+ int ret;
- clk = clk_register_fixed_rate(NULL, "s2f_usr_clk", NULL, CLK_IS_ROOT, SOCFPGA_S2F_USR_CLK);
- clk_register_clkdev(clk, "s2f_usr_clk", NULL);
+ clk = clk_register_fixed_factor(NULL, "smp_twd", "mpuclk", 0, 1, 4);
+ ret = clk_register_clkdev(clk, NULL, "smp_twd");
+ if (ret)
+ pr_err("smp_twd alias not registered\n");
}
--
1.7.9.5
More information about the linux-arm-kernel
mailing list