ARM: 6597/1: Add basic architecture support for VIA/WonderMedia 85xx SoC's
This adds support for the family of Systems-on-Chip produced initially
by VIA and now its subsidiary WonderMedia that have recently become
widespread in lower-end Chinese ARM-based tablets and netbooks.
Support is included for both VT8500 and WM8505, selectable by a
configuration switch at kernel build time.
Included are basic machine initialization files, register and
interrupt definitions, support for the on-chip interrupt controller,
high-precision OS timer, GPIO lines, necessary macros for early debug,
pulse-width-modulated outputs control, as well as platform device
configurations for the specific drivers implemented elsewhere.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-vt8500/irq.c b/arch/arm/mach-vt8500/irq.c
new file mode 100644
index 0000000..5f4ddde
--- /dev/null
+++ b/arch/arm/mach-vt8500/irq.c
@@ -0,0 +1,177 @@
+/*
+ * arch/arm/mach-vt8500/irq.c
+ *
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+
+#include <asm/irq.h>
+
+#include "devices.h"
+
+#define VT8500_IC_DCTR 0x40 /* Destination control
+ register, 64*u8 */
+#define VT8500_INT_ENABLE (1 << 3)
+#define VT8500_TRIGGER_HIGH (0 << 4)
+#define VT8500_TRIGGER_RISING (1 << 4)
+#define VT8500_TRIGGER_FALLING (2 << 4)
+#define VT8500_EDGE ( VT8500_TRIGGER_RISING \
+ | VT8500_TRIGGER_FALLING)
+#define VT8500_IC_STATUS 0x80 /* Interrupt status, 2*u32 */
+
+static void __iomem *ic_regbase;
+static void __iomem *sic_regbase;
+
+static void vt8500_irq_mask(unsigned int irq)
+{
+ void __iomem *base = ic_regbase;
+ u8 edge;
+
+ if (irq >= 64) {
+ base = sic_regbase;
+ irq -= 64;
+ }
+ edge = readb(base + VT8500_IC_DCTR + irq) & VT8500_EDGE;
+ if (edge) {
+ void __iomem *stat_reg = base + VT8500_IC_STATUS
+ + (irq < 32 ? 0 : 4);
+ unsigned status = readl(stat_reg);
+
+ status |= (1 << (irq & 0x1f));
+ writel(status, stat_reg);
+ } else {
+ u8 dctr = readb(base + VT8500_IC_DCTR + irq);
+
+ dctr &= ~VT8500_INT_ENABLE;
+ writeb(dctr, base + VT8500_IC_DCTR + irq);
+ }
+}
+
+static void vt8500_irq_unmask(unsigned int irq)
+{
+ void __iomem *base = ic_regbase;
+ u8 dctr;
+
+ if (irq >= 64) {
+ base = sic_regbase;
+ irq -= 64;
+ }
+ dctr = readb(base + VT8500_IC_DCTR + irq);
+ dctr |= VT8500_INT_ENABLE;
+ writeb(dctr, base + VT8500_IC_DCTR + irq);
+}
+
+static int vt8500_irq_set_type(unsigned int irq, unsigned int flow_type)
+{
+ void __iomem *base = ic_regbase;
+ unsigned int orig_irq = irq;
+ u8 dctr;
+
+ if (irq >= 64) {
+ base = sic_regbase;
+ irq -= 64;
+ }
+
+ dctr = readb(base + VT8500_IC_DCTR + irq);
+ dctr &= ~VT8500_EDGE;
+
+ switch (flow_type) {
+ case IRQF_TRIGGER_LOW:
+ return -EINVAL;
+ case IRQF_TRIGGER_HIGH:
+ dctr |= VT8500_TRIGGER_HIGH;
+ irq_desc[orig_irq].handle_irq = handle_level_irq;
+ break;
+ case IRQF_TRIGGER_FALLING:
+ dctr |= VT8500_TRIGGER_FALLING;
+ irq_desc[orig_irq].handle_irq = handle_edge_irq;
+ break;
+ case IRQF_TRIGGER_RISING:
+ dctr |= VT8500_TRIGGER_RISING;
+ irq_desc[orig_irq].handle_irq = handle_edge_irq;
+ break;
+ }
+ writeb(dctr, base + VT8500_IC_DCTR + irq);
+
+ return 0;
+}
+
+static struct irq_chip vt8500_irq_chip = {
+ .name = "vt8500",
+ .ack = vt8500_irq_mask,
+ .mask = vt8500_irq_mask,
+ .unmask = vt8500_irq_unmask,
+ .set_type = vt8500_irq_set_type,
+};
+
+void __init vt8500_init_irq(void)
+{
+ unsigned int i;
+
+ ic_regbase = ioremap(wmt_ic_base, SZ_64K);
+
+ if (ic_regbase) {
+ /* Enable rotating priority for IRQ */
+ writel((1 << 6), ic_regbase + 0x20);
+ writel(0, ic_regbase + 0x24);
+
+ for (i = 0; i < wmt_nr_irqs; i++) {
+ /* Disable all interrupts and route them to IRQ */
+ writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
+
+ set_irq_chip(i, &vt8500_irq_chip);
+ set_irq_handler(i, handle_level_irq);
+ set_irq_flags(i, IRQF_VALID);
+ }
+ } else {
+ printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
+ }
+}
+
+void __init wm8505_init_irq(void)
+{
+ unsigned int i;
+
+ ic_regbase = ioremap(wmt_ic_base, SZ_64K);
+ sic_regbase = ioremap(wmt_sic_base, SZ_64K);
+
+ if (ic_regbase && sic_regbase) {
+ /* Enable rotating priority for IRQ */
+ writel((1 << 6), ic_regbase + 0x20);
+ writel(0, ic_regbase + 0x24);
+ writel((1 << 6), sic_regbase + 0x20);
+ writel(0, sic_regbase + 0x24);
+
+ for (i = 0; i < wmt_nr_irqs; i++) {
+ /* Disable all interrupts and route them to IRQ */
+ if (i < 64)
+ writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
+ else
+ writeb(0x00, sic_regbase + VT8500_IC_DCTR
+ + i - 64);
+
+ set_irq_chip(i, &vt8500_irq_chip);
+ set_irq_handler(i, handle_level_irq);
+ set_irq_flags(i, IRQF_VALID);
+ }
+ } else {
+ printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
+ }
+}