MIPS: Add initial support for the Atheros AR71XX/AR724X/AR931X SoCs
This patch adds initial support for various Atheros SoCs based on the
MIPS 24Kc core. The following models are supported at the moment:
- AR7130
- AR7141
- AR7161
- AR9130
- AR9132
- AR7240
- AR7241
- AR7242
The current patch contains minimal support only, but the resulting
kernel can boot into user-space with using of an initramfs image on
various boards which are using these SoCs. Support for more built-in
devices and individual boards will be implemented in further patches.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Imre Kaloz <kaloz@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Luis R. Rodriguez <lrodriguez@atheros.com>
Cc: Cliff Holden <Cliff.Holden@Atheros.com>
Cc: Kathy Giori <Kathy.Giori@Atheros.com>
Patchwork: https://patchwork.linux-mips.org/patch/1947/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/ath79/clock.c b/arch/mips/ath79/clock.c
new file mode 100644
index 0000000..680bde9
--- /dev/null
+++ b/arch/mips/ath79/clock.c
@@ -0,0 +1,183 @@
+/*
+ * Atheros AR71XX/AR724X/AR913X common routines
+ *
+ * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+
+#include <asm/mach-ath79/ath79.h>
+#include <asm/mach-ath79/ar71xx_regs.h>
+#include "common.h"
+
+#define AR71XX_BASE_FREQ 40000000
+#define AR724X_BASE_FREQ 5000000
+#define AR913X_BASE_FREQ 5000000
+
+struct clk {
+ unsigned long rate;
+};
+
+static struct clk ath79_ref_clk;
+static struct clk ath79_cpu_clk;
+static struct clk ath79_ddr_clk;
+static struct clk ath79_ahb_clk;
+static struct clk ath79_wdt_clk;
+static struct clk ath79_uart_clk;
+
+static void __init ar71xx_clocks_init(void)
+{
+ u32 pll;
+ u32 freq;
+ u32 div;
+
+ ath79_ref_clk.rate = AR71XX_BASE_FREQ;
+
+ pll = ath79_pll_rr(AR71XX_PLL_REG_CPU_CONFIG);
+
+ div = ((pll >> AR71XX_PLL_DIV_SHIFT) & AR71XX_PLL_DIV_MASK) + 1;
+ freq = div * ath79_ref_clk.rate;
+
+ div = ((pll >> AR71XX_CPU_DIV_SHIFT) & AR71XX_CPU_DIV_MASK) + 1;
+ ath79_cpu_clk.rate = freq / div;
+
+ div = ((pll >> AR71XX_DDR_DIV_SHIFT) & AR71XX_DDR_DIV_MASK) + 1;
+ ath79_ddr_clk.rate = freq / div;
+
+ div = (((pll >> AR71XX_AHB_DIV_SHIFT) & AR71XX_AHB_DIV_MASK) + 1) * 2;
+ ath79_ahb_clk.rate = ath79_cpu_clk.rate / div;
+
+ ath79_wdt_clk.rate = ath79_ahb_clk.rate;
+ ath79_uart_clk.rate = ath79_ahb_clk.rate;
+}
+
+static void __init ar724x_clocks_init(void)
+{
+ u32 pll;
+ u32 freq;
+ u32 div;
+
+ ath79_ref_clk.rate = AR724X_BASE_FREQ;
+ pll = ath79_pll_rr(AR724X_PLL_REG_CPU_CONFIG);
+
+ div = ((pll >> AR724X_PLL_DIV_SHIFT) & AR724X_PLL_DIV_MASK);
+ freq = div * ath79_ref_clk.rate;
+
+ div = ((pll >> AR724X_PLL_REF_DIV_SHIFT) & AR724X_PLL_REF_DIV_MASK);
+ freq *= div;
+
+ ath79_cpu_clk.rate = freq;
+
+ div = ((pll >> AR724X_DDR_DIV_SHIFT) & AR724X_DDR_DIV_MASK) + 1;
+ ath79_ddr_clk.rate = freq / div;
+
+ div = (((pll >> AR724X_AHB_DIV_SHIFT) & AR724X_AHB_DIV_MASK) + 1) * 2;
+ ath79_ahb_clk.rate = ath79_cpu_clk.rate / div;
+
+ ath79_wdt_clk.rate = ath79_ahb_clk.rate;
+ ath79_uart_clk.rate = ath79_ahb_clk.rate;
+}
+
+static void __init ar913x_clocks_init(void)
+{
+ u32 pll;
+ u32 freq;
+ u32 div;
+
+ ath79_ref_clk.rate = AR913X_BASE_FREQ;
+ pll = ath79_pll_rr(AR913X_PLL_REG_CPU_CONFIG);
+
+ div = ((pll >> AR913X_PLL_DIV_SHIFT) & AR913X_PLL_DIV_MASK);
+ freq = div * ath79_ref_clk.rate;
+
+ ath79_cpu_clk.rate = freq;
+
+ div = ((pll >> AR913X_DDR_DIV_SHIFT) & AR913X_DDR_DIV_MASK) + 1;
+ ath79_ddr_clk.rate = freq / div;
+
+ div = (((pll >> AR913X_AHB_DIV_SHIFT) & AR913X_AHB_DIV_MASK) + 1) * 2;
+ ath79_ahb_clk.rate = ath79_cpu_clk.rate / div;
+
+ ath79_wdt_clk.rate = ath79_ahb_clk.rate;
+ ath79_uart_clk.rate = ath79_ahb_clk.rate;
+}
+
+void __init ath79_clocks_init(void)
+{
+ if (soc_is_ar71xx())
+ ar71xx_clocks_init();
+ else if (soc_is_ar724x())
+ ar724x_clocks_init();
+ else if (soc_is_ar913x())
+ ar913x_clocks_init();
+ else
+ BUG();
+
+ pr_info("Clocks: CPU:%lu.%03luMHz, DDR:%lu.%03luMHz, AHB:%lu.%03luMHz, "
+ "Ref:%lu.%03luMHz",
+ ath79_cpu_clk.rate / 1000000,
+ (ath79_cpu_clk.rate / 1000) % 1000,
+ ath79_ddr_clk.rate / 1000000,
+ (ath79_ddr_clk.rate / 1000) % 1000,
+ ath79_ahb_clk.rate / 1000000,
+ (ath79_ahb_clk.rate / 1000) % 1000,
+ ath79_ref_clk.rate / 1000000,
+ (ath79_ref_clk.rate / 1000) % 1000);
+}
+
+/*
+ * Linux clock API
+ */
+struct clk *clk_get(struct device *dev, const char *id)
+{
+ if (!strcmp(id, "ref"))
+ return &ath79_ref_clk;
+
+ if (!strcmp(id, "cpu"))
+ return &ath79_cpu_clk;
+
+ if (!strcmp(id, "ddr"))
+ return &ath79_ddr_clk;
+
+ if (!strcmp(id, "ahb"))
+ return &ath79_ahb_clk;
+
+ if (!strcmp(id, "wdt"))
+ return &ath79_wdt_clk;
+
+ if (!strcmp(id, "uart"))
+ return &ath79_uart_clk;
+
+ return ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL(clk_get);
+
+int clk_enable(struct clk *clk)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+void clk_put(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_put);