Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 184 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/powermac/udbg_scc.c b/arch/powerpc/platforms/powermac/udbg_scc.c
new file mode 100644
index 000000000..1b7c39e84
--- /dev/null
+++ b/arch/powerpc/platforms/powermac/udbg_scc.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * udbg for zilog scc ports as found on Apple PowerMacs
+ *
+ * Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
+ */
+#include <linux/types.h>
+#include <linux/of.h>
+#include <asm/udbg.h>
+#include <asm/processor.h>
+#include <asm/io.h>
+#include <asm/pmac_feature.h>
+
+extern u8 real_readb(volatile u8 __iomem  *addr);
+extern void real_writeb(u8 data, volatile u8 __iomem *addr);
+
+#define	SCC_TXRDY	4
+#define SCC_RXRDY	1
+
+static volatile u8 __iomem *sccc;
+static volatile u8 __iomem *sccd;
+
+static void udbg_scc_putc(char c)
+{
+	if (sccc) {
+		while ((in_8(sccc) & SCC_TXRDY) == 0)
+			;
+		out_8(sccd,  c);
+		if (c == '\n')
+			udbg_scc_putc('\r');
+	}
+}
+
+static int udbg_scc_getc_poll(void)
+{
+	if (sccc) {
+		if ((in_8(sccc) & SCC_RXRDY) != 0)
+			return in_8(sccd);
+		else
+			return -1;
+	}
+	return -1;
+}
+
+static int udbg_scc_getc(void)
+{
+	if (sccc) {
+		while ((in_8(sccc) & SCC_RXRDY) == 0)
+			;
+		return in_8(sccd);
+	}
+	return -1;
+}
+
+static unsigned char scc_inittab[] = {
+    13, 0,		/* set baud rate divisor */
+    12, 0,
+    14, 1,		/* baud rate gen enable, src=rtxc */
+    11, 0x50,		/* clocks = br gen */
+    5,  0xea,		/* tx 8 bits, assert DTR & RTS */
+    4,  0x46,		/* x16 clock, 1 stop */
+    3,  0xc1,		/* rx enable, 8 bits */
+};
+
+void __init udbg_scc_init(int force_scc)
+{
+	const u32 *reg;
+	unsigned long addr;
+	struct device_node *stdout = NULL, *escc = NULL, *macio = NULL;
+	struct device_node *ch, *ch_def = NULL, *ch_a = NULL;
+	const char *path;
+	int i;
+
+	escc = of_find_node_by_name(NULL, "escc");
+	if (escc == NULL)
+		goto bail;
+	macio = of_get_parent(escc);
+	if (macio == NULL)
+		goto bail;
+	path = of_get_property(of_chosen, "linux,stdout-path", NULL);
+	if (path != NULL)
+		stdout = of_find_node_by_path(path);
+	for_each_child_of_node(escc, ch) {
+		if (ch == stdout) {
+			of_node_put(ch_def);
+			ch_def = of_node_get(ch);
+		}
+		if (of_node_name_eq(ch, "ch-a")) {
+			of_node_put(ch_a);
+			ch_a = of_node_get(ch);
+		}
+	}
+	if (ch_def == NULL && !force_scc)
+		goto bail;
+
+	ch = ch_def ? ch_def : ch_a;
+
+	/* Get address within mac-io ASIC */
+	reg = of_get_property(escc, "reg", NULL);
+	if (reg == NULL)
+		goto bail;
+	addr = reg[0];
+
+	/* Get address of mac-io PCI itself */
+	reg = of_get_property(macio, "assigned-addresses", NULL);
+	if (reg == NULL)
+		goto bail;
+	addr += reg[2];
+
+	/* Lock the serial port */
+	pmac_call_feature(PMAC_FTR_SCC_ENABLE, ch,
+			  PMAC_SCC_ASYNC | PMAC_SCC_FLAG_XMON, 1);
+
+	if (ch == ch_a)
+		addr += 0x20;
+	sccc = ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
+	sccc += addr & ~PAGE_MASK;
+	sccd = sccc + 0x10;
+
+	mb();
+
+	for (i = 20000; i != 0; --i)
+		in_8(sccc);
+	out_8(sccc, 0x09);		/* reset A or B side */
+	out_8(sccc, 0xc0);
+
+	/* If SCC was the OF output port, read the BRG value, else
+	 * Setup for 38400 or 57600 8N1 depending on the machine
+	 */
+	if (ch_def != NULL) {
+		out_8(sccc, 13);
+		scc_inittab[1] = in_8(sccc);
+		out_8(sccc, 12);
+		scc_inittab[3] = in_8(sccc);
+	} else if (of_machine_is_compatible("RackMac1,1")
+		   || of_machine_is_compatible("RackMac1,2")
+		   || of_machine_is_compatible("MacRISC4")) {
+		/* Xserves and G5s default to 57600 */
+		scc_inittab[1] = 0;
+		scc_inittab[3] = 0;
+	} else {
+		/* Others default to 38400 */
+		scc_inittab[1] = 0;
+		scc_inittab[3] = 1;
+	}
+
+	for (i = 0; i < sizeof(scc_inittab); ++i)
+		out_8(sccc, scc_inittab[i]);
+
+
+	udbg_putc = udbg_scc_putc;
+	udbg_getc = udbg_scc_getc;
+	udbg_getc_poll = udbg_scc_getc_poll;
+
+	udbg_puts("Hello World !\n");
+
+ bail:
+	of_node_put(macio);
+	of_node_put(escc);
+	of_node_put(stdout);
+	of_node_put(ch_def);
+	of_node_put(ch_a);
+}
+
+#ifdef CONFIG_PPC64
+static void udbg_real_scc_putc(char c)
+{
+	while ((real_readb(sccc) & SCC_TXRDY) == 0)
+		;
+	real_writeb(c, sccd);
+	if (c == '\n')
+		udbg_real_scc_putc('\r');
+}
+
+void __init udbg_init_pmac_realmode(void)
+{
+	sccc = (volatile u8 __iomem *)0x80013020ul;
+	sccd = (volatile u8 __iomem *)0x80013030ul;
+
+	udbg_putc = udbg_real_scc_putc;
+	udbg_getc = NULL;
+	udbg_getc_poll = NULL;
+}
+#endif /* CONFIG_PPC64 */