Adding upstream version 4.19.249.upstream/4.19.249upstream

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

1 files changed, 466 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
new file mode 100644
index 000000000..1d9b8aaea
--- /dev/null
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <asm/dma.h>
+#include <linux/io.h>
+#include <asm/processor-cyrix.h>
+#include <asm/processor-flags.h>
+#include <linux/timer.h>
+#include <asm/pci-direct.h>
+#include <asm/tsc.h>
+#include <asm/cpufeature.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#include "cpu.h"
+
+/*
+ * Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
+ */
+static void __do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+	unsigned char ccr2, ccr3;
+
+	/* we test for DEVID by checking whether CCR3 is writable */
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, ccr3 ^ 0x80);
+	getCx86(0xc0);   /* dummy to change bus */
+
+	if (getCx86(CX86_CCR3) == ccr3) {       /* no DEVID regs. */
+		ccr2 = getCx86(CX86_CCR2);
+		setCx86(CX86_CCR2, ccr2 ^ 0x04);
+		getCx86(0xc0);  /* dummy */
+
+		if (getCx86(CX86_CCR2) == ccr2) /* old Cx486SLC/DLC */
+			*dir0 = 0xfd;
+		else {                          /* Cx486S A step */
+			setCx86(CX86_CCR2, ccr2);
+			*dir0 = 0xfe;
+		}
+	} else {
+		setCx86(CX86_CCR3, ccr3);  /* restore CCR3 */
+
+		/* read DIR0 and DIR1 CPU registers */
+		*dir0 = getCx86(CX86_DIR0);
+		*dir1 = getCx86(CX86_DIR1);
+	}
+}
+
+static void do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	__do_cyrix_devid(dir0, dir1);
+	local_irq_restore(flags);
+}
+/*
+ * Cx86_dir0_msb is a HACK needed by check_cx686_cpuid/slop in bugs.h in
+ * order to identify the Cyrix CPU model after we're out of setup.c
+ *
+ * Actually since bugs.h doesn't even reference this perhaps someone should
+ * fix the documentation ???
+ */
+static unsigned char Cx86_dir0_msb = 0;
+
+static const char Cx86_model[][9] = {
+	"Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
+	"M II ", "Unknown"
+};
+static const char Cx486_name[][5] = {
+	"SLC", "DLC", "SLC2", "DLC2", "SRx", "DRx",
+	"SRx2", "DRx2"
+};
+static const char Cx486S_name[][4] = {
+	"S", "S2", "Se", "S2e"
+};
+static const char Cx486D_name[][4] = {
+	"DX", "DX2", "?", "?", "?", "DX4"
+};
+static char Cx86_cb[] = "?.5x Core/Bus Clock";
+static const char cyrix_model_mult1[] = "12??43";
+static const char cyrix_model_mult2[] = "12233445";
+
+/*
+ * Reset the slow-loop (SLOP) bit on the 686(L) which is set by some old
+ * BIOSes for compatibility with DOS games.  This makes the udelay loop
+ * work correctly, and improves performance.
+ *
+ * FIXME: our newer udelay uses the tsc. We don't need to frob with SLOP
+ */
+
+static void check_cx686_slop(struct cpuinfo_x86 *c)
+{
+	unsigned long flags;
+
+	if (Cx86_dir0_msb == 3) {
+		unsigned char ccr3, ccr5;
+
+		local_irq_save(flags);
+		ccr3 = getCx86(CX86_CCR3);
+		setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+		ccr5 = getCx86(CX86_CCR5);
+		if (ccr5 & 2)
+			setCx86(CX86_CCR5, ccr5 & 0xfd);  /* reset SLOP */
+		setCx86(CX86_CCR3, ccr3);                 /* disable MAPEN */
+		local_irq_restore(flags);
+
+		if (ccr5 & 2) { /* possible wrong calibration done */
+			pr_info("Recalibrating delay loop with SLOP bit reset\n");
+			calibrate_delay();
+			c->loops_per_jiffy = loops_per_jiffy;
+		}
+	}
+}
+
+
+static void set_cx86_reorder(void)
+{
+	u8 ccr3;
+
+	pr_info("Enable Memory access reorder on Cyrix/NSC processor.\n");
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+
+	/* Load/Store Serialize to mem access disable (=reorder it) */
+	setCx86(CX86_PCR0, getCx86(CX86_PCR0) & ~0x80);
+	/* set load/store serialize from 1GB to 4GB */
+	ccr3 |= 0xe0;
+	setCx86(CX86_CCR3, ccr3);
+}
+
+static void set_cx86_memwb(void)
+{
+	pr_info("Enable Memory-Write-back mode on Cyrix/NSC processor.\n");
+
+	/* CCR2 bit 2: unlock NW bit */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) & ~0x04);
+	/* set 'Not Write-through' */
+	write_cr0(read_cr0() | X86_CR0_NW);
+	/* CCR2 bit 2: lock NW bit and set WT1 */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
+}
+
+/*
+ *	Configure later MediaGX and/or Geode processor.
+ */
+
+static void geode_configure(void)
+{
+	unsigned long flags;
+	u8 ccr3;
+	local_irq_save(flags);
+
+	/* Suspend on halt power saving and enable #SUSP pin */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
+
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);	/* enable MAPEN */
+
+
+	/* FPU fast, DTE cache, Mem bypass */
+	setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x38);
+	setCx86(CX86_CCR3, ccr3);			/* disable MAPEN */
+
+	set_cx86_memwb();
+	set_cx86_reorder();
+
+	local_irq_restore(flags);
+}
+
+static void early_init_cyrix(struct cpuinfo_x86 *c)
+{
+	unsigned char dir0, dir0_msn, dir1 = 0;
+
+	__do_cyrix_devid(&dir0, &dir1);
+	dir0_msn = dir0 >> 4; /* identifies CPU "family"   */
+
+	switch (dir0_msn) {
+	case 3: /* 6x86/6x86L */
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+	case 5: /* 6x86MX/M II */
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+	}
+}
+
+static void init_cyrix(struct cpuinfo_x86 *c)
+{
+	unsigned char dir0, dir0_msn, dir0_lsn, dir1 = 0;
+	char *buf = c->x86_model_id;
+	const char *p = NULL;
+
+	/*
+	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+	 */
+	clear_cpu_cap(c, 0*32+31);
+
+	/* Cyrix used bit 24 in extended (AMD) CPUID for Cyrix MMX extensions */
+	if (test_cpu_cap(c, 1*32+24)) {
+		clear_cpu_cap(c, 1*32+24);
+		set_cpu_cap(c, X86_FEATURE_CXMMX);
+	}
+
+	do_cyrix_devid(&dir0, &dir1);
+
+	check_cx686_slop(c);
+
+	Cx86_dir0_msb = dir0_msn = dir0 >> 4; /* identifies CPU "family"   */
+	dir0_lsn = dir0 & 0xf;                /* model or clock multiplier */
+
+	/* common case step number/rev -- exceptions handled below */
+	c->x86_model = (dir1 >> 4) + 1;
+	c->x86_stepping = dir1 & 0xf;
+
+	/* Now cook; the original recipe is by Channing Corn, from Cyrix.
+	 * We do the same thing for each generation: we work out
+	 * the model, multiplier and stepping.  Black magic included,
+	 * to make the silicon step/rev numbers match the printed ones.
+	 */
+
+	switch (dir0_msn) {
+		unsigned char tmp;
+
+	case 0: /* Cx486SLC/DLC/SRx/DRx */
+		p = Cx486_name[dir0_lsn & 7];
+		break;
+
+	case 1: /* Cx486S/DX/DX2/DX4 */
+		p = (dir0_lsn & 8) ? Cx486D_name[dir0_lsn & 5]
+			: Cx486S_name[dir0_lsn & 3];
+		break;
+
+	case 2: /* 5x86 */
+		Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+		p = Cx86_cb+2;
+		break;
+
+	case 3: /* 6x86/6x86L */
+		Cx86_cb[1] = ' ';
+		Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+		if (dir1 > 0x21) { /* 686L */
+			Cx86_cb[0] = 'L';
+			p = Cx86_cb;
+			(c->x86_model)++;
+		} else             /* 686 */
+			p = Cx86_cb+1;
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		/* 6x86's contain this bug */
+		set_cpu_bug(c, X86_BUG_COMA);
+		break;
+
+	case 4: /* MediaGX/GXm or Geode GXM/GXLV/GX1 */
+	case 11: /* GX1 with inverted Device ID */
+#ifdef CONFIG_PCI
+	{
+		u32 vendor, device;
+		/*
+		 * It isn't really a PCI quirk directly, but the cure is the
+		 * same. The MediaGX has deep magic SMM stuff that handles the
+		 * SB emulation. It throws away the fifo on disable_dma() which
+		 * is wrong and ruins the audio.
+		 *
+		 *  Bug2: VSA1 has a wrap bug so that using maximum sized DMA
+		 *  causes bad things. According to NatSemi VSA2 has another
+		 *  bug to do with 'hlt'. I've not seen any boards using VSA2
+		 *  and X doesn't seem to support it either so who cares 8).
+		 *  VSA1 we work around however.
+		 */
+
+		pr_info("Working around Cyrix MediaGX virtual DMA bugs.\n");
+		isa_dma_bridge_buggy = 2;
+
+		/* We do this before the PCI layer is running. However we
+		   are safe here as we know the bridge must be a Cyrix
+		   companion and must be present */
+		vendor = read_pci_config_16(0, 0, 0x12, PCI_VENDOR_ID);
+		device = read_pci_config_16(0, 0, 0x12, PCI_DEVICE_ID);
+
+		/*
+		 *  The 5510/5520 companion chips have a funky PIT.
+		 */
+		if (vendor == PCI_VENDOR_ID_CYRIX &&
+			(device == PCI_DEVICE_ID_CYRIX_5510 ||
+					device == PCI_DEVICE_ID_CYRIX_5520))
+			mark_tsc_unstable("cyrix 5510/5520 detected");
+	}
+#endif
+		c->x86_cache_size = 16;	/* Yep 16K integrated cache thats it */
+
+		/* GXm supports extended cpuid levels 'ala' AMD */
+		if (c->cpuid_level == 2) {
+			/* Enable cxMMX extensions (GX1 Datasheet 54) */
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
+
+			/*
+			 * GXm : 0x30 ... 0x5f GXm  datasheet 51
+			 * GXlv: 0x6x          GXlv datasheet 54
+			 *  ?  : 0x7x
+			 * GX1 : 0x8x          GX1  datasheet 56
+			 */
+			if ((0x30 <= dir1 && dir1 <= 0x6f) ||
+					(0x80 <= dir1 && dir1 <= 0x8f))
+				geode_configure();
+			return;
+		} else { /* MediaGX */
+			Cx86_cb[2] = (dir0_lsn & 1) ? '3' : '4';
+			p = Cx86_cb+2;
+			c->x86_model = (dir1 & 0x20) ? 1 : 2;
+		}
+		break;
+
+	case 5: /* 6x86MX/M II */
+		if (dir1 > 7) {
+			dir0_msn++;  /* M II */
+			/* Enable MMX extensions (App note 108) */
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7)|1);
+		} else {
+			/* A 6x86MX - it has the bug. */
+			set_cpu_bug(c, X86_BUG_COMA);
+		}
+		tmp = (!(dir0_lsn & 7) || dir0_lsn & 1) ? 2 : 0;
+		Cx86_cb[tmp] = cyrix_model_mult2[dir0_lsn & 7];
+		p = Cx86_cb+tmp;
+		if (((dir1 & 0x0f) > 4) || ((dir1 & 0xf0) == 0x20))
+			(c->x86_model)++;
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+
+	case 0xf:  /* Cyrix 486 without DEVID registers */
+		switch (dir0_lsn) {
+		case 0xd:  /* either a 486SLC or DLC w/o DEVID */
+			dir0_msn = 0;
+			p = Cx486_name[!!boot_cpu_has(X86_FEATURE_FPU)];
+			break;
+
+		case 0xe:  /* a 486S A step */
+			dir0_msn = 0;
+			p = Cx486S_name[0];
+			break;
+		}
+		break;
+
+	default:  /* unknown (shouldn't happen, we know everyone ;-) */
+		dir0_msn = 7;
+		break;
+	}
+	strcpy(buf, Cx86_model[dir0_msn & 7]);
+	if (p)
+		strcat(buf, p);
+	return;
+}
+
+/*
+ * Handle National Semiconductor branded processors
+ */
+static void init_nsc(struct cpuinfo_x86 *c)
+{
+	/*
+	 * There may be GX1 processors in the wild that are branded
+	 * NSC and not Cyrix.
+	 *
+	 * This function only handles the GX processor, and kicks every
+	 * thing else to the Cyrix init function above - that should
+	 * cover any processors that might have been branded differently
+	 * after NSC acquired Cyrix.
+	 *
+	 * If this breaks your GX1 horribly, please e-mail
+	 * info-linux@ldcmail.amd.com to tell us.
+	 */
+
+	/* Handle the GX (Formally known as the GX2) */
+
+	if (c->x86 == 5 && c->x86_model == 5)
+		cpu_detect_cache_sizes(c);
+	else
+		init_cyrix(c);
+}
+
+/*
+ * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
+ * by the fact that they preserve the flags across the division of 5/2.
+ * PII and PPro exhibit this behavior too, but they have cpuid available.
+ */
+
+/*
+ * Perform the Cyrix 5/2 test. A Cyrix won't change
+ * the flags, while other 486 chips will.
+ */
+static inline int test_cyrix_52div(void)
+{
+	unsigned int test;
+
+	__asm__ __volatile__(
+	     "sahf\n\t"		/* clear flags (%eax = 0x0005) */
+	     "div %b2\n\t"	/* divide 5 by 2 */
+	     "lahf"		/* store flags into %ah */
+	     : "=a" (test)
+	     : "0" (5), "q" (2)
+	     : "cc");
+
+	/* AH is 0x02 on Cyrix after the divide.. */
+	return (unsigned char) (test >> 8) == 0x02;
+}
+
+static void cyrix_identify(struct cpuinfo_x86 *c)
+{
+	/* Detect Cyrix with disabled CPUID */
+	if (c->x86 == 4 && test_cyrix_52div()) {
+		unsigned char dir0, dir1;
+
+		strcpy(c->x86_vendor_id, "CyrixInstead");
+		c->x86_vendor = X86_VENDOR_CYRIX;
+
+		/* Actually enable cpuid on the older cyrix */
+
+		/* Retrieve CPU revisions */
+
+		do_cyrix_devid(&dir0, &dir1);
+
+		dir0 >>= 4;
+
+		/* Check it is an affected model */
+
+		if (dir0 == 5 || dir0 == 3) {
+			unsigned char ccr3;
+			unsigned long flags;
+			pr_info("Enabling CPUID on Cyrix processor.\n");
+			local_irq_save(flags);
+			ccr3 = getCx86(CX86_CCR3);
+			/* enable MAPEN  */
+			setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
+			/* enable cpuid  */
+			setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x80);
+			/* disable MAPEN */
+			setCx86(CX86_CCR3, ccr3);
+			local_irq_restore(flags);
+		}
+	}
+}
+
+static const struct cpu_dev cyrix_cpu_dev = {
+	.c_vendor	= "Cyrix",
+	.c_ident	= { "CyrixInstead" },
+	.c_early_init	= early_init_cyrix,
+	.c_init		= init_cyrix,
+	.c_identify	= cyrix_identify,
+	.c_x86_vendor	= X86_VENDOR_CYRIX,
+};
+
+cpu_dev_register(cyrix_cpu_dev);
+
+static const struct cpu_dev nsc_cpu_dev = {
+	.c_vendor	= "NSC",
+	.c_ident	= { "Geode by NSC" },
+	.c_init		= init_nsc,
+	.c_x86_vendor	= X86_VENDOR_NSC,
+};
+
+cpu_dev_register(nsc_cpu_dev);