cpu: add CPU driver for Broadcom MIPS SoCs

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/cpu/bmips_cpu.c b/drivers/cpu/bmips_cpu.c
new file mode 100644
index 0000000..379acf2
--- /dev/null
+++ b/drivers/cpu/bmips_cpu.c
@@ -0,0 +1,310 @@
+/*
+ * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * Derived from linux/arch/mips/bcm63xx/cpu.c:
+ *	Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ *	Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define REV_CHIPID_SHIFT		16
+#define REV_CHIPID_MASK			(0xffff << REV_CHIPID_SHIFT)
+#define REV_LONG_CHIPID_SHIFT		12
+#define REV_LONG_CHIPID_MASK		(0xfffff << REV_LONG_CHIPID_SHIFT)
+#define REV_REVID_SHIFT			0
+#define REV_REVID_MASK			(0xff << REV_REVID_SHIFT)
+
+#define REG_BCM6328_OTP			0x62c
+#define BCM6328_TP1_DISABLED		BIT(9)
+
+#define REG_BCM6328_MISC_STRAPBUS	0x1a40
+#define STRAPBUS_6328_FCVO_SHIFT	7
+#define STRAPBUS_6328_FCVO_MASK		(0x1f << STRAPBUS_6328_FCVO_SHIFT)
+
+#define REG_BCM6358_DDR_DMIPSPLLCFG	0x12b8
+#define DMIPSPLLCFG_6358_M1_SHIFT	0
+#define DMIPSPLLCFG_6358_M1_MASK	(0xff << DMIPSPLLCFG_6358_M1_SHIFT)
+#define DMIPSPLLCFG_6358_N1_SHIFT	23
+#define DMIPSPLLCFG_6358_N1_MASK	(0x3f << DMIPSPLLCFG_6358_N1_SHIFT)
+#define DMIPSPLLCFG_6358_N2_SHIFT	29
+#define DMIPSPLLCFG_6358_N2_MASK	(0x7 << DMIPSPLLCFG_6358_N2_SHIFT)
+
+#define REG_BCM63268_MISC_STRAPBUS	0x1814
+#define STRAPBUS_63268_FCVO_SHIFT	21
+#define STRAPBUS_63268_FCVO_MASK	(0xf << STRAPBUS_63268_FCVO_SHIFT)
+
+struct bmips_cpu_priv;
+
+struct bmips_cpu_hw {
+	int (*get_cpu_desc)(struct bmips_cpu_priv *priv, char *buf, int size);
+	ulong (*get_cpu_freq)(struct bmips_cpu_priv *);
+	int (*get_cpu_count)(struct bmips_cpu_priv *);
+};
+
+struct bmips_cpu_priv {
+	void __iomem *regs;
+	const struct bmips_cpu_hw *hw;
+};
+
+/* Specific CPU Ops */
+static int bcm6358_get_cpu_desc(struct bmips_cpu_priv *priv, char *buf,
+				int size)
+{
+	unsigned short cpu_id;
+	unsigned char cpu_rev;
+	u32 val;
+
+	val = readl_be(priv->regs);
+	cpu_id = (val & REV_CHIPID_MASK) >> REV_CHIPID_SHIFT;
+	cpu_rev = (val & REV_REVID_MASK) >> REV_REVID_SHIFT;
+
+	snprintf(buf, size, "BCM%04X%02X", cpu_id, cpu_rev);
+
+	return 0;
+}
+
+static int bcm6328_get_cpu_desc(struct bmips_cpu_priv *priv, char *buf,
+				int size)
+{
+	unsigned int cpu_id;
+	unsigned char cpu_rev;
+	u32 val;
+
+	val = readl_be(priv->regs);
+	cpu_id = (val & REV_LONG_CHIPID_MASK) >> REV_LONG_CHIPID_SHIFT;
+	cpu_rev = (val & REV_REVID_MASK) >> REV_REVID_SHIFT;
+
+	snprintf(buf, size, "BCM%05X%02X", cpu_id, cpu_rev);
+
+	return 0;
+}
+
+static ulong bcm6328_get_cpu_freq(struct bmips_cpu_priv *priv)
+{
+	unsigned int mips_pll_fcvo;
+
+	mips_pll_fcvo = readl_be(priv->regs + REG_BCM6328_MISC_STRAPBUS);
+	mips_pll_fcvo = (mips_pll_fcvo & STRAPBUS_6328_FCVO_MASK)
+			>> STRAPBUS_6328_FCVO_SHIFT;
+
+	switch (mips_pll_fcvo) {
+	case 0x12:
+	case 0x14:
+	case 0x19:
+		return 160000000;
+	case 0x1c:
+		return 192000000;
+	case 0x13:
+	case 0x15:
+		return 200000000;
+	case 0x1a:
+		return 384000000;
+	case 0x16:
+		return 400000000;
+	default:
+		return 320000000;
+	}
+}
+
+static ulong bcm6358_get_cpu_freq(struct bmips_cpu_priv *priv)
+{
+	unsigned int tmp, n1, n2, m1;
+
+	tmp = readl_be(priv->regs + REG_BCM6358_DDR_DMIPSPLLCFG);
+	n1 = (tmp & DMIPSPLLCFG_6358_N1_MASK) >> DMIPSPLLCFG_6358_N1_SHIFT;
+	n2 = (tmp & DMIPSPLLCFG_6358_N2_MASK) >> DMIPSPLLCFG_6358_N2_SHIFT;
+	m1 = (tmp & DMIPSPLLCFG_6358_M1_MASK) >> DMIPSPLLCFG_6358_M1_SHIFT;
+
+	return (16 * 1000000 * n1 * n2) / m1;
+}
+
+static ulong bcm63268_get_cpu_freq(struct bmips_cpu_priv *priv)
+{
+	unsigned int mips_pll_fcvo;
+
+	mips_pll_fcvo = readl_be(priv->regs + REG_BCM63268_MISC_STRAPBUS);
+	mips_pll_fcvo = (mips_pll_fcvo & STRAPBUS_63268_FCVO_MASK)
+			>> STRAPBUS_63268_FCVO_SHIFT;
+
+	switch (mips_pll_fcvo) {
+	case 0x3:
+	case 0xe:
+		return 320000000;
+	case 0xa:
+		return 333000000;
+	case 0x2:
+	case 0xb:
+	case 0xf:
+		return 400000000;
+	default:
+		return 0;
+	}
+}
+
+static int bcm6328_get_cpu_count(struct bmips_cpu_priv *priv)
+{
+	u32 val = readl_be(priv->regs + REG_BCM6328_OTP);
+
+	if (val & BCM6328_TP1_DISABLED)
+		return 1;
+	else
+		return 2;
+}
+
+static int bcm6358_get_cpu_count(struct bmips_cpu_priv *priv)
+{
+	return 2;
+}
+
+static const struct bmips_cpu_hw bmips_cpu_bcm6328 = {
+	.get_cpu_desc = bcm6328_get_cpu_desc,
+	.get_cpu_freq = bcm6328_get_cpu_freq,
+	.get_cpu_count = bcm6328_get_cpu_count,
+};
+
+static const struct bmips_cpu_hw bmips_cpu_bcm6358 = {
+	.get_cpu_desc = bcm6358_get_cpu_desc,
+	.get_cpu_freq = bcm6358_get_cpu_freq,
+	.get_cpu_count = bcm6358_get_cpu_count,
+};
+
+static const struct bmips_cpu_hw bmips_cpu_bcm63268 = {
+	.get_cpu_desc = bcm6328_get_cpu_desc,
+	.get_cpu_freq = bcm63268_get_cpu_freq,
+	.get_cpu_count = bcm6358_get_cpu_count,
+};
+
+/* Generic CPU Ops */
+static int bmips_cpu_get_desc(struct udevice *dev, char *buf, int size)
+{
+	struct bmips_cpu_priv *priv = dev_get_priv(dev);
+	const struct bmips_cpu_hw *hw = priv->hw;
+
+	return hw->get_cpu_desc(priv, buf, size);
+}
+
+static int bmips_cpu_get_info(struct udevice *dev, struct cpu_info *info)
+{
+	struct bmips_cpu_priv *priv = dev_get_priv(dev);
+	const struct bmips_cpu_hw *hw = priv->hw;
+
+	info->cpu_freq = hw->get_cpu_freq(priv);
+	info->features = BIT(CPU_FEAT_L1_CACHE);
+	info->features |= BIT(CPU_FEAT_MMU);
+	info->features |= BIT(CPU_FEAT_DEVICE_ID);
+
+	return 0;
+}
+
+static int bmips_cpu_get_count(struct udevice *dev)
+{
+	struct bmips_cpu_priv *priv = dev_get_priv(dev);
+	const struct bmips_cpu_hw *hw = priv->hw;
+
+	return hw->get_cpu_count(priv);
+}
+
+static int bmips_cpu_get_vendor(struct udevice *dev, char *buf, int size)
+{
+	snprintf(buf, size, "Broadcom");
+
+	return 0;
+}
+
+static const struct cpu_ops bmips_cpu_ops = {
+	.get_desc = bmips_cpu_get_desc,
+	.get_info = bmips_cpu_get_info,
+	.get_count = bmips_cpu_get_count,
+	.get_vendor = bmips_cpu_get_vendor,
+};
+
+/* BMIPS CPU driver */
+int bmips_cpu_bind(struct udevice *dev)
+{
+	struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+	plat->cpu_id = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
+		"reg", -1);
+	plat->device_id = read_c0_prid();
+
+	return 0;
+}
+
+int bmips_cpu_probe(struct udevice *dev)
+{
+	struct bmips_cpu_priv *priv = dev_get_priv(dev);
+	const struct bmips_cpu_hw *hw =
+		(const struct bmips_cpu_hw *)dev_get_driver_data(dev);
+	fdt_addr_t addr;
+	fdt_size_t size;
+
+	addr = dev_get_addr_size_index(dev_get_parent(dev), 0, &size);
+	if (addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	priv->regs = ioremap(addr, size);
+	priv->hw = hw;
+
+	return 0;
+}
+
+static const struct udevice_id bmips_cpu_ids[] = {
+	{
+		.compatible = "brcm,bcm6328-cpu",
+		.data = (ulong)&bmips_cpu_bcm6328,
+	}, {
+		.compatible = "brcm,bcm6358-cpu",
+		.data = (ulong)&bmips_cpu_bcm6358,
+	}, {
+		.compatible = "brcm,bcm63268-cpu",
+		.data = (ulong)&bmips_cpu_bcm63268,
+	},
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(bmips_cpu_drv) = {
+	.name = "bmips_cpu",
+	.id = UCLASS_CPU,
+	.of_match = bmips_cpu_ids,
+	.bind = bmips_cpu_bind,
+	.probe = bmips_cpu_probe,
+	.priv_auto_alloc_size = sizeof(struct bmips_cpu_priv),
+	.ops = &bmips_cpu_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
+
+#ifdef CONFIG_DISPLAY_CPUINFO
+int print_cpuinfo(void)
+{
+	struct cpu_info cpu;
+	struct udevice *dev;
+	int err;
+	char desc[100];
+
+	err = uclass_get_device(UCLASS_CPU, 0, &dev);
+	if (err)
+		return 0;
+
+	err = cpu_get_info(dev, &cpu);
+	if (err)
+		return 0;
+
+	err = cpu_get_desc(dev, desc, sizeof(desc));
+	if (err)
+		return 0;
+
+	printf("Chip ID: %s, MIPS: ", desc);
+	print_freq(cpu.cpu_freq, "\n");
+
+	return 0;
+}
+#endif