omap iommu: omap2 architecture specific functions

The structure 'arch_mmu' accommodates the difference between omap1 and
omap2/3.

This patch provides omap2/3 specific functions

Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

1 files changed, 323 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c
new file mode 100644
index 0000000..015f22a
--- /dev/null
+++ b/arch/arm/mach-omap2/iommu2.c
@@ -0,0 +1,323 @@
+/*
+ * omap iommu: omap2/3 architecture specific functions
+ *
+ * Copyright (C) 2008-2009 Nokia Corporation
+ *
+ * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
+ *		Paul Mundt and Toshihiro Kobayashi
+ *
+ * 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/err.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/stringify.h>
+
+#include <mach/iommu.h>
+
+/*
+ * omap2 architecture specific register bit definitions
+ */
+#define IOMMU_ARCH_VERSION	0x00000011
+
+/* SYSCONF */
+#define MMU_SYS_IDLE_SHIFT	3
+#define MMU_SYS_IDLE_FORCE	(0 << MMU_SYS_IDLE_SHIFT)
+#define MMU_SYS_IDLE_NONE	(1 << MMU_SYS_IDLE_SHIFT)
+#define MMU_SYS_IDLE_SMART	(2 << MMU_SYS_IDLE_SHIFT)
+#define MMU_SYS_IDLE_MASK	(3 << MMU_SYS_IDLE_SHIFT)
+
+#define MMU_SYS_SOFTRESET	(1 << 1)
+#define MMU_SYS_AUTOIDLE	1
+
+/* SYSSTATUS */
+#define MMU_SYS_RESETDONE	1
+
+/* IRQSTATUS & IRQENABLE */
+#define MMU_IRQ_MULTIHITFAULT	(1 << 4)
+#define MMU_IRQ_TABLEWALKFAULT	(1 << 3)
+#define MMU_IRQ_EMUMISS		(1 << 2)
+#define MMU_IRQ_TRANSLATIONFAULT	(1 << 1)
+#define MMU_IRQ_TLBMISS		(1 << 0)
+#define MMU_IRQ_MASK	\
+	(MMU_IRQ_MULTIHITFAULT | MMU_IRQ_TABLEWALKFAULT | MMU_IRQ_EMUMISS | \
+	 MMU_IRQ_TRANSLATIONFAULT)
+
+/* MMU_CNTL */
+#define MMU_CNTL_SHIFT		1
+#define MMU_CNTL_MASK		(7 << MMU_CNTL_SHIFT)
+#define MMU_CNTL_EML_TLB	(1 << 3)
+#define MMU_CNTL_TWL_EN		(1 << 2)
+#define MMU_CNTL_MMU_EN		(1 << 1)
+
+#define get_cam_va_mask(pgsz)				\
+	(((pgsz) == MMU_CAM_PGSZ_16M) ? 0xff000000 :	\
+	 ((pgsz) == MMU_CAM_PGSZ_1M)  ? 0xfff00000 :	\
+	 ((pgsz) == MMU_CAM_PGSZ_64K) ? 0xffff0000 :	\
+	 ((pgsz) == MMU_CAM_PGSZ_4K)  ? 0xfffff000 : 0)
+
+static int omap2_iommu_enable(struct iommu *obj)
+{
+	u32 l, pa;
+	unsigned long timeout;
+
+	if (!obj->iopgd || !IS_ALIGNED((u32)obj->iopgd,  SZ_16K))
+		return -EINVAL;
+
+	pa = virt_to_phys(obj->iopgd);
+	if (!IS_ALIGNED(pa, SZ_16K))
+		return -EINVAL;
+
+	iommu_write_reg(obj, MMU_SYS_SOFTRESET, MMU_SYSCONFIG);
+
+	timeout = jiffies + msecs_to_jiffies(20);
+	do {
+		l = iommu_read_reg(obj, MMU_SYSSTATUS);
+		if (l & MMU_SYS_RESETDONE)
+			break;
+	} while (time_after(jiffies, timeout));
+
+	if (!(l & MMU_SYS_RESETDONE)) {
+		dev_err(obj->dev, "can't take mmu out of reset\n");
+		return -ENODEV;
+	}
+
+	l = iommu_read_reg(obj, MMU_REVISION);
+	dev_info(obj->dev, "%s: version %d.%d\n", obj->name,
+		 (l >> 4) & 0xf, l & 0xf);
+
+	l = iommu_read_reg(obj, MMU_SYSCONFIG);
+	l &= ~MMU_SYS_IDLE_MASK;
+	l |= (MMU_SYS_IDLE_SMART | MMU_SYS_AUTOIDLE);
+	iommu_write_reg(obj, l, MMU_SYSCONFIG);
+
+	iommu_write_reg(obj, MMU_IRQ_MASK, MMU_IRQENABLE);
+	iommu_write_reg(obj, pa, MMU_TTB);
+
+	l = iommu_read_reg(obj, MMU_CNTL);
+	l &= ~MMU_CNTL_MASK;
+	l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN);
+	iommu_write_reg(obj, l, MMU_CNTL);
+
+	return 0;
+}
+
+static void omap2_iommu_disable(struct iommu *obj)
+{
+	u32 l = iommu_read_reg(obj, MMU_CNTL);
+
+	l &= ~MMU_CNTL_MASK;
+	iommu_write_reg(obj, l, MMU_CNTL);
+	iommu_write_reg(obj, MMU_SYS_IDLE_FORCE, MMU_SYSCONFIG);
+
+	dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
+}
+
+static u32 omap2_iommu_fault_isr(struct iommu *obj, u32 *ra)
+{
+	int i;
+	u32 stat, da;
+	const char *err_msg[] =	{
+		"tlb miss",
+		"translation fault",
+		"emulation miss",
+		"table walk fault",
+		"multi hit fault",
+	};
+
+	stat = iommu_read_reg(obj, MMU_IRQSTATUS);
+	stat &= MMU_IRQ_MASK;
+	if (!stat)
+		return 0;
+
+	da = iommu_read_reg(obj, MMU_FAULT_AD);
+	*ra = da;
+
+	dev_err(obj->dev, "%s:\tda:%08x ", __func__, da);
+
+	for (i = 0; i < ARRAY_SIZE(err_msg); i++) {
+		if (stat & (1 << i))
+			printk("%s ", err_msg[i]);
+	}
+	printk("\n");
+
+	iommu_write_reg(obj, stat, MMU_IRQSTATUS);
+	return stat;
+}
+
+static void omap2_tlb_read_cr(struct iommu *obj, struct cr_regs *cr)
+{
+	cr->cam = iommu_read_reg(obj, MMU_READ_CAM);
+	cr->ram = iommu_read_reg(obj, MMU_READ_RAM);
+}
+
+static void omap2_tlb_load_cr(struct iommu *obj, struct cr_regs *cr)
+{
+	iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM);
+	iommu_write_reg(obj, cr->ram, MMU_RAM);
+}
+
+static u32 omap2_cr_to_virt(struct cr_regs *cr)
+{
+	u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK;
+	u32 mask = get_cam_va_mask(cr->cam & page_size);
+
+	return cr->cam & mask;
+}
+
+static struct cr_regs *omap2_alloc_cr(struct iommu *obj, struct iotlb_entry *e)
+{
+	struct cr_regs *cr;
+
+	if (e->da & ~(get_cam_va_mask(e->pgsz))) {
+		dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__,
+			e->da);
+		return ERR_PTR(-EINVAL);
+	}
+
+	cr = kmalloc(sizeof(*cr), GFP_KERNEL);
+	if (!cr)
+		return ERR_PTR(-ENOMEM);
+
+	cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz;
+	cr->ram = e->pa | e->endian | e->elsz | e->mixed;
+
+	return cr;
+}
+
+static inline int omap2_cr_valid(struct cr_regs *cr)
+{
+	return cr->cam & MMU_CAM_V;
+}
+
+static u32 omap2_get_pte_attr(struct iotlb_entry *e)
+{
+	u32 attr;
+
+	attr = e->mixed << 5;
+	attr |= e->endian;
+	attr |= e->elsz >> 3;
+	attr <<= ((e->pgsz & MMU_CAM_PGSZ_4K) ? 0 : 6);
+
+	return attr;
+}
+
+static ssize_t omap2_dump_cr(struct iommu *obj, struct cr_regs *cr, char *buf)
+{
+	char *p = buf;
+
+	/* FIXME: Need more detail analysis of cam/ram */
+	p += sprintf(p, "%08x %08x\n", cr->cam, cr->ram);
+
+	return p - buf;
+}
+
+#define pr_reg(name)							\
+	p += sprintf(p, "%20s: %08x\n",					\
+		     __stringify(name), iommu_read_reg(obj, MMU_##name));
+
+static ssize_t omap2_iommu_dump_ctx(struct iommu *obj, char *buf)
+{
+	char *p = buf;
+
+	pr_reg(REVISION);
+	pr_reg(SYSCONFIG);
+	pr_reg(SYSSTATUS);
+	pr_reg(IRQSTATUS);
+	pr_reg(IRQENABLE);
+	pr_reg(WALKING_ST);
+	pr_reg(CNTL);
+	pr_reg(FAULT_AD);
+	pr_reg(TTB);
+	pr_reg(LOCK);
+	pr_reg(LD_TLB);
+	pr_reg(CAM);
+	pr_reg(RAM);
+	pr_reg(GFLUSH);
+	pr_reg(FLUSH_ENTRY);
+	pr_reg(READ_CAM);
+	pr_reg(READ_RAM);
+	pr_reg(EMU_FAULT_AD);
+
+	return p - buf;
+}
+
+static void omap2_iommu_save_ctx(struct iommu *obj)
+{
+	int i;
+	u32 *p = obj->ctx;
+
+	for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
+		p[i] = iommu_read_reg(obj, i * sizeof(u32));
+		dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]);
+	}
+
+	BUG_ON(p[0] != IOMMU_ARCH_VERSION);
+}
+
+static void omap2_iommu_restore_ctx(struct iommu *obj)
+{
+	int i;
+	u32 *p = obj->ctx;
+
+	for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
+		iommu_write_reg(obj, p[i], i * sizeof(u32));
+		dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]);
+	}
+
+	BUG_ON(p[0] != IOMMU_ARCH_VERSION);
+}
+
+static void omap2_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
+{
+	e->da		= cr->cam & MMU_CAM_VATAG_MASK;
+	e->pa		= cr->ram & MMU_RAM_PADDR_MASK;
+	e->valid	= cr->cam & MMU_CAM_V;
+	e->pgsz		= cr->cam & MMU_CAM_PGSZ_MASK;
+	e->endian	= cr->ram & MMU_RAM_ENDIAN_MASK;
+	e->elsz		= cr->ram & MMU_RAM_ELSZ_MASK;
+	e->mixed	= cr->ram & MMU_RAM_MIXED;
+}
+
+static const struct iommu_functions omap2_iommu_ops = {
+	.version	= IOMMU_ARCH_VERSION,
+
+	.enable		= omap2_iommu_enable,
+	.disable	= omap2_iommu_disable,
+	.fault_isr	= omap2_iommu_fault_isr,
+
+	.tlb_read_cr	= omap2_tlb_read_cr,
+	.tlb_load_cr	= omap2_tlb_load_cr,
+
+	.cr_to_e	= omap2_cr_to_e,
+	.cr_to_virt	= omap2_cr_to_virt,
+	.alloc_cr	= omap2_alloc_cr,
+	.cr_valid	= omap2_cr_valid,
+	.dump_cr	= omap2_dump_cr,
+
+	.get_pte_attr	= omap2_get_pte_attr,
+
+	.save_ctx	= omap2_iommu_save_ctx,
+	.restore_ctx	= omap2_iommu_restore_ctx,
+	.dump_ctx	= omap2_iommu_dump_ctx,
+};
+
+static int __init omap2_iommu_init(void)
+{
+	return install_iommu_arch(&omap2_iommu_ops);
+}
+module_init(omap2_iommu_init);
+
+static void __exit omap2_iommu_exit(void)
+{
+	uninstall_iommu_arch(&omap2_iommu_ops);
+}
+module_exit(omap2_iommu_exit);
+
+MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi");
+MODULE_DESCRIPTION("omap iommu: omap2/3 architecture specific functions");
+MODULE_LICENSE("GPL v2");