1 files changed, 506 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/512x/mpc512x_shared.c b/arch/powerpc/platforms/512x/mpc512x_shared.c
new file mode 100644
index 000000000..5ac0ead25
--- /dev/null
+++ b/arch/powerpc/platforms/512x/mpc512x_shared.c
@@ -0,0 +1,506 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2007,2008 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author: John Rigby <jrigby@freescale.com>
+ *
+ * Description:
+ * MPC512x Shared code
+ */
+
+#include <linux/clk.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/fsl-diu-fb.h>
+#include <linux/memblock.h>
+#include <sysdev/fsl_soc.h>
+
+#include <asm/cacheflush.h>
+#include <asm/machdep.h>
+#include <asm/ipic.h>
+#include <asm/time.h>
+#include <asm/mpc5121.h>
+#include <asm/mpc52xx_psc.h>
+
+#include "mpc512x.h"
+
+static struct mpc512x_reset_module __iomem *reset_module_base;
+
+static void __init mpc512x_restart_init(void)
+{
+	struct device_node *np;
+	const char *reset_compat;
+
+	reset_compat = mpc512x_select_reset_compat();
+	np = of_find_compatible_node(NULL, NULL, reset_compat);
+	if (!np)
+		return;
+
+	reset_module_base = of_iomap(np, 0);
+	of_node_put(np);
+}
+
+void __noreturn mpc512x_restart(char *cmd)
+{
+	if (reset_module_base) {
+		/* Enable software reset "RSTE" */
+		out_be32(&reset_module_base->rpr, 0x52535445);
+		/* Set software hard reset */
+		out_be32(&reset_module_base->rcr, 0x2);
+	} else {
+		pr_err("Restart module not mapped.\n");
+	}
+	for (;;)
+		;
+}
+
+struct fsl_diu_shared_fb {
+	u8		gamma[0x300];	/* 32-bit aligned! */
+	struct diu_ad	ad0;		/* 32-bit aligned! */
+	phys_addr_t	fb_phys;
+	size_t		fb_len;
+	bool		in_use;
+};
+
+/* receives a pixel clock spec in pico seconds, adjusts the DIU clock rate */
+static void mpc512x_set_pixel_clock(unsigned int pixclock)
+{
+	struct device_node *np;
+	struct clk *clk_diu;
+	unsigned long epsilon, minpixclock, maxpixclock;
+	unsigned long offset, want, got, delta;
+
+	/* lookup and enable the DIU clock */
+	np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu");
+	if (!np) {
+		pr_err("Could not find DIU device tree node.\n");
+		return;
+	}
+	clk_diu = of_clk_get(np, 0);
+	if (IS_ERR(clk_diu)) {
+		/* backwards compat with device trees that lack clock specs */
+		clk_diu = clk_get_sys(np->name, "ipg");
+	}
+	of_node_put(np);
+	if (IS_ERR(clk_diu)) {
+		pr_err("Could not lookup DIU clock.\n");
+		return;
+	}
+	if (clk_prepare_enable(clk_diu)) {
+		pr_err("Could not enable DIU clock.\n");
+		return;
+	}
+
+	/*
+	 * convert the picoseconds spec into the desired clock rate,
+	 * determine the acceptable clock range for the monitor (+/- 5%),
+	 * do the calculation in steps to avoid integer overflow
+	 */
+	pr_debug("DIU pixclock in ps - %u\n", pixclock);
+	pixclock = (1000000000 / pixclock) * 1000;
+	pr_debug("DIU pixclock freq  - %u\n", pixclock);
+	epsilon = pixclock / 20; /* pixclock * 0.05 */
+	pr_debug("DIU deviation      - %lu\n", epsilon);
+	minpixclock = pixclock - epsilon;
+	maxpixclock = pixclock + epsilon;
+	pr_debug("DIU minpixclock    - %lu\n", minpixclock);
+	pr_debug("DIU maxpixclock    - %lu\n", maxpixclock);
+
+	/*
+	 * check whether the DIU supports the desired pixel clock
+	 *
+	 * - simply request the desired clock and see what the
+	 *   platform's clock driver will make of it, assuming that it
+	 *   will setup the best approximation of the requested value
+	 * - try other candidate frequencies in the order of decreasing
+	 *   preference (i.e. with increasing distance from the desired
+	 *   pixel clock, and checking the lower frequency before the
+	 *   higher frequency to not overload the hardware) until the
+	 *   first match is found -- any potential subsequent match
+	 *   would only be as good as the former match or typically
+	 *   would be less preferrable
+	 *
+	 * the offset increment of pixelclock divided by 64 is an
+	 * arbitrary choice -- it's simple to calculate, in the typical
+	 * case we expect the first check to succeed already, in the
+	 * worst case seven frequencies get tested (the exact center and
+	 * three more values each to the left and to the right) before
+	 * the 5% tolerance window is exceeded, resulting in fast enough
+	 * execution yet high enough probability of finding a suitable
+	 * value, while the error rate will be in the order of single
+	 * percents
+	 */
+	for (offset = 0; offset <= epsilon; offset += pixclock / 64) {
+		want = pixclock - offset;
+		pr_debug("DIU checking clock - %lu\n", want);
+		clk_set_rate(clk_diu, want);
+		got = clk_get_rate(clk_diu);
+		delta = abs(pixclock - got);
+		if (delta < epsilon)
+			break;
+		if (!offset)
+			continue;
+		want = pixclock + offset;
+		pr_debug("DIU checking clock - %lu\n", want);
+		clk_set_rate(clk_diu, want);
+		got = clk_get_rate(clk_diu);
+		delta = abs(pixclock - got);
+		if (delta < epsilon)
+			break;
+	}
+	if (offset <= epsilon) {
+		pr_debug("DIU clock accepted - %lu\n", want);
+		pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n",
+			 pixclock, got, delta, epsilon);
+		return;
+	}
+	pr_warn("DIU pixclock auto search unsuccessful\n");
+
+	/*
+	 * what is the most appropriate action to take when the search
+	 * for an available pixel clock which is acceptable to the
+	 * monitor has failed?  disable the DIU (clock) or just provide
+	 * a "best effort"?  we go with the latter
+	 */
+	pr_warn("DIU pixclock best effort fallback (backend's choice)\n");
+	clk_set_rate(clk_diu, pixclock);
+	got = clk_get_rate(clk_diu);
+	delta = abs(pixclock - got);
+	pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n",
+		 pixclock, got, delta, epsilon);
+}
+
+static enum fsl_diu_monitor_port
+mpc512x_valid_monitor_port(enum fsl_diu_monitor_port port)
+{
+	return FSL_DIU_PORT_DVI;
+}
+
+static struct fsl_diu_shared_fb __attribute__ ((__aligned__(8))) diu_shared_fb;
+
+static inline void mpc512x_free_bootmem(struct page *page)
+{
+	BUG_ON(PageTail(page));
+	BUG_ON(page_ref_count(page) > 1);
+	free_reserved_page(page);
+}
+
+static void mpc512x_release_bootmem(void)
+{
+	unsigned long addr = diu_shared_fb.fb_phys & PAGE_MASK;
+	unsigned long size = diu_shared_fb.fb_len;
+	unsigned long start, end;
+
+	if (diu_shared_fb.in_use) {
+		start = PFN_UP(addr);
+		end = PFN_DOWN(addr + size);
+
+		for (; start < end; start++)
+			mpc512x_free_bootmem(pfn_to_page(start));
+
+		diu_shared_fb.in_use = false;
+	}
+	diu_ops.release_bootmem	= NULL;
+}
+
+/*
+ * Check if DIU was pre-initialized. If so, perform steps
+ * needed to continue displaying through the whole boot process.
+ * Move area descriptor and gamma table elsewhere, they are
+ * destroyed by bootmem allocator otherwise. The frame buffer
+ * address range will be reserved in setup_arch() after bootmem
+ * allocator is up.
+ */
+static void __init mpc512x_init_diu(void)
+{
+	struct device_node *np;
+	struct diu __iomem *diu_reg;
+	phys_addr_t desc;
+	void __iomem *vaddr;
+	unsigned long mode, pix_fmt, res, bpp;
+	unsigned long dst;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu");
+	if (!np) {
+		pr_err("No DIU node\n");
+		return;
+	}
+
+	diu_reg = of_iomap(np, 0);
+	of_node_put(np);
+	if (!diu_reg) {
+		pr_err("Can't map DIU\n");
+		return;
+	}
+
+	mode = in_be32(&diu_reg->diu_mode);
+	if (mode == MFB_MODE0) {
+		pr_info("%s: DIU OFF\n", __func__);
+		goto out;
+	}
+
+	desc = in_be32(&diu_reg->desc[0]);
+	vaddr = ioremap(desc, sizeof(struct diu_ad));
+	if (!vaddr) {
+		pr_err("Can't map DIU area desc.\n");
+		goto out;
+	}
+	memcpy(&diu_shared_fb.ad0, vaddr, sizeof(struct diu_ad));
+	/* flush fb area descriptor */
+	dst = (unsigned long)&diu_shared_fb.ad0;
+	flush_dcache_range(dst, dst + sizeof(struct diu_ad) - 1);
+
+	res = in_be32(&diu_reg->disp_size);
+	pix_fmt = in_le32(vaddr);
+	bpp = ((pix_fmt >> 16) & 0x3) + 1;
+	diu_shared_fb.fb_phys = in_le32(vaddr + 4);
+	diu_shared_fb.fb_len = ((res & 0xfff0000) >> 16) * (res & 0xfff) * bpp;
+	diu_shared_fb.in_use = true;
+	iounmap(vaddr);
+
+	desc = in_be32(&diu_reg->gamma);
+	vaddr = ioremap(desc, sizeof(diu_shared_fb.gamma));
+	if (!vaddr) {
+		pr_err("Can't map DIU area desc.\n");
+		diu_shared_fb.in_use = false;
+		goto out;
+	}
+	memcpy(&diu_shared_fb.gamma, vaddr, sizeof(diu_shared_fb.gamma));
+	/* flush gamma table */
+	dst = (unsigned long)&diu_shared_fb.gamma;
+	flush_dcache_range(dst, dst + sizeof(diu_shared_fb.gamma) - 1);
+
+	iounmap(vaddr);
+	out_be32(&diu_reg->gamma, virt_to_phys(&diu_shared_fb.gamma));
+	out_be32(&diu_reg->desc[1], 0);
+	out_be32(&diu_reg->desc[2], 0);
+	out_be32(&diu_reg->desc[0], virt_to_phys(&diu_shared_fb.ad0));
+
+out:
+	iounmap(diu_reg);
+}
+
+static void __init mpc512x_setup_diu(void)
+{
+	int ret;
+
+	/*
+	 * We do not allocate and configure new area for bitmap buffer
+	 * because it would require copying bitmap data (splash image)
+	 * and so negatively affect boot time. Instead we reserve the
+	 * already configured frame buffer area so that it won't be
+	 * destroyed. The starting address of the area to reserve and
+	 * also it's length is passed to memblock_reserve(). It will be
+	 * freed later on first open of fbdev, when splash image is not
+	 * needed any more.
+	 */
+	if (diu_shared_fb.in_use) {
+		ret = memblock_reserve(diu_shared_fb.fb_phys,
+				       diu_shared_fb.fb_len);
+		if (ret) {
+			pr_err("%s: reserve bootmem failed\n", __func__);
+			diu_shared_fb.in_use = false;
+		}
+	}
+
+	diu_ops.set_pixel_clock		= mpc512x_set_pixel_clock;
+	diu_ops.valid_monitor_port	= mpc512x_valid_monitor_port;
+	diu_ops.release_bootmem		= mpc512x_release_bootmem;
+}
+
+void __init mpc512x_init_IRQ(void)
+{
+	struct device_node *np;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-ipic");
+	if (!np)
+		return;
+
+	ipic_init(np, 0);
+	of_node_put(np);
+
+	/*
+	 * Initialize the default interrupt mapping priorities,
+	 * in case the boot rom changed something on us.
+	 */
+	ipic_set_default_priority();
+}
+
+/*
+ * Nodes to do bus probe on, soc and localbus
+ */
+static const struct of_device_id of_bus_ids[] __initconst = {
+	{ .compatible = "fsl,mpc5121-immr", },
+	{ .compatible = "fsl,mpc5121-localbus", },
+	{ .compatible = "fsl,mpc5121-mbx", },
+	{ .compatible = "fsl,mpc5121-nfc", },
+	{ .compatible = "fsl,mpc5121-sram", },
+	{ .compatible = "fsl,mpc5121-pci", },
+	{ .compatible = "gpio-leds", },
+	{},
+};
+
+static void __init mpc512x_declare_of_platform_devices(void)
+{
+	if (of_platform_bus_probe(NULL, of_bus_ids, NULL))
+		printk(KERN_ERR __FILE__ ": "
+			"Error while probing of_platform bus\n");
+}
+
+#define DEFAULT_FIFO_SIZE 16
+
+const char *__init mpc512x_select_psc_compat(void)
+{
+	if (of_machine_is_compatible("fsl,mpc5121"))
+		return "fsl,mpc5121-psc";
+
+	if (of_machine_is_compatible("fsl,mpc5125"))
+		return "fsl,mpc5125-psc";
+
+	return NULL;
+}
+
+const char *__init mpc512x_select_reset_compat(void)
+{
+	if (of_machine_is_compatible("fsl,mpc5121"))
+		return "fsl,mpc5121-reset";
+
+	if (of_machine_is_compatible("fsl,mpc5125"))
+		return "fsl,mpc5125-reset";
+
+	return NULL;
+}
+
+static unsigned int __init get_fifo_size(struct device_node *np,
+					 char *prop_name)
+{
+	const unsigned int *fp;
+
+	fp = of_get_property(np, prop_name, NULL);
+	if (fp)
+		return *fp;
+
+	pr_warn("no %s property in %pOF node, defaulting to %d\n",
+		prop_name, np, DEFAULT_FIFO_SIZE);
+
+	return DEFAULT_FIFO_SIZE;
+}
+
+#define FIFOC(_base) ((struct mpc512x_psc_fifo __iomem *) \
+		    ((u32)(_base) + sizeof(struct mpc52xx_psc)))
+
+/* Init PSC FIFO space for TX and RX slices */
+static void __init mpc512x_psc_fifo_init(void)
+{
+	struct device_node *np;
+	void __iomem *psc;
+	unsigned int tx_fifo_size;
+	unsigned int rx_fifo_size;
+	const char *psc_compat;
+	int fifobase = 0; /* current fifo address in 32 bit words */
+
+	psc_compat = mpc512x_select_psc_compat();
+	if (!psc_compat) {
+		pr_err("%s: no compatible devices found\n", __func__);
+		return;
+	}
+
+	for_each_compatible_node(np, NULL, psc_compat) {
+		tx_fifo_size = get_fifo_size(np, "fsl,tx-fifo-size");
+		rx_fifo_size = get_fifo_size(np, "fsl,rx-fifo-size");
+
+		/* size in register is in 4 byte units */
+		tx_fifo_size /= 4;
+		rx_fifo_size /= 4;
+		if (!tx_fifo_size)
+			tx_fifo_size = 1;
+		if (!rx_fifo_size)
+			rx_fifo_size = 1;
+
+		psc = of_iomap(np, 0);
+		if (!psc) {
+			pr_err("%s: Can't map %pOF device\n",
+				__func__, np);
+			continue;
+		}
+
+		/* FIFO space is 4KiB, check if requested size is available */
+		if ((fifobase + tx_fifo_size + rx_fifo_size) > 0x1000) {
+			pr_err("%s: no fifo space available for %pOF\n",
+				__func__, np);
+			iounmap(psc);
+			/*
+			 * chances are that another device requests less
+			 * fifo space, so we continue.
+			 */
+			continue;
+		}
+
+		/* set tx and rx fifo size registers */
+		out_be32(&FIFOC(psc)->txsz, (fifobase << 16) | tx_fifo_size);
+		fifobase += tx_fifo_size;
+		out_be32(&FIFOC(psc)->rxsz, (fifobase << 16) | rx_fifo_size);
+		fifobase += rx_fifo_size;
+
+		/* reset and enable the slices */
+		out_be32(&FIFOC(psc)->txcmd, 0x80);
+		out_be32(&FIFOC(psc)->txcmd, 0x01);
+		out_be32(&FIFOC(psc)->rxcmd, 0x80);
+		out_be32(&FIFOC(psc)->rxcmd, 0x01);
+
+		iounmap(psc);
+	}
+}
+
+void __init mpc512x_init_early(void)
+{
+	mpc512x_restart_init();
+	if (IS_ENABLED(CONFIG_FB_FSL_DIU))
+		mpc512x_init_diu();
+}
+
+void __init mpc512x_init(void)
+{
+	mpc5121_clk_init();
+	mpc512x_declare_of_platform_devices();
+	mpc512x_psc_fifo_init();
+}
+
+void __init mpc512x_setup_arch(void)
+{
+	if (IS_ENABLED(CONFIG_FB_FSL_DIU))
+		mpc512x_setup_diu();
+}
+
+/**
+ * mpc512x_cs_config - Setup chip select configuration
+ * @cs: chip select number
+ * @val: chip select configuration value
+ *
+ * Perform chip select configuration for devices on LocalPlus Bus.
+ * Intended to dynamically reconfigure the chip select parameters
+ * for configurable devices on the bus.
+ */
+int mpc512x_cs_config(unsigned int cs, u32 val)
+{
+	static struct mpc512x_lpc __iomem *lpc;
+	struct device_node *np;
+
+	if (cs > 7)
+		return -EINVAL;
+
+	if (!lpc) {
+		np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-lpc");
+		lpc = of_iomap(np, 0);
+		of_node_put(np);
+		if (!lpc)
+			return -ENOMEM;
+	}
+
+	out_be32(&lpc->cs_cfg[cs], val);
+	return 0;
+}
+EXPORT_SYMBOL(mpc512x_cs_config);