Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 227 insertions, 0 deletions

diff --git a/arch/mips/loongson64/cpucfg-emul.c b/arch/mips/loongson64/cpucfg-emul.c
new file mode 100644
index 0000000000..630927e46d
--- /dev/null
+++ b/arch/mips/loongson64/cpucfg-emul.c
@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/smp.h>
+#include <linux/types.h>
+#include <asm/cpu.h>
+#include <asm/cpu-info.h>
+#include <asm/elf.h>
+
+#include <loongson_regs.h>
+#include <cpucfg-emul.h>
+
+static bool is_loongson(struct cpuinfo_mips *c)
+{
+	switch (c->processor_id & PRID_COMP_MASK) {
+	case PRID_COMP_LEGACY:
+		return ((c->processor_id & PRID_IMP_MASK) ==
+			PRID_IMP_LOONGSON_64C);
+
+	case PRID_COMP_LOONGSON:
+		return true;
+
+	default:
+		return false;
+	}
+}
+
+static u32 get_loongson_fprev(struct cpuinfo_mips *c)
+{
+	return c->fpu_id & LOONGSON_FPREV_MASK;
+}
+
+static bool cpu_has_uca(void)
+{
+	u32 diag = read_c0_diag();
+	u32 new_diag;
+
+	if (diag & LOONGSON_DIAG_UCAC)
+		/* UCA is already enabled. */
+		return true;
+
+	/* See if UCAC bit can be flipped on. This should be safe. */
+	new_diag = diag | LOONGSON_DIAG_UCAC;
+	write_c0_diag(new_diag);
+	new_diag = read_c0_diag();
+	write_c0_diag(diag);
+
+	return (new_diag & LOONGSON_DIAG_UCAC) != 0;
+}
+
+static void probe_uca(struct cpuinfo_mips *c)
+{
+	if (cpu_has_uca())
+		c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_LSUCA;
+}
+
+static void decode_loongson_config6(struct cpuinfo_mips *c)
+{
+	u32 config6 = read_c0_config6();
+
+	if (config6 & LOONGSON_CONF6_SFBEN)
+		c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_SFBP;
+	if (config6 & LOONGSON_CONF6_LLEXC)
+		c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_LLEXC;
+	if (config6 & LOONGSON_CONF6_SCRAND)
+		c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_SCRAND;
+}
+
+static void patch_cpucfg_sel1(struct cpuinfo_mips *c)
+{
+	u64 ases = c->ases;
+	u64 options = c->options;
+	u32 data = c->loongson3_cpucfg_data[0];
+
+	if (options & MIPS_CPU_FPU) {
+		data |= LOONGSON_CFG1_FP;
+		data |= get_loongson_fprev(c) << LOONGSON_CFG1_FPREV_OFFSET;
+	}
+	if (ases & MIPS_ASE_LOONGSON_MMI)
+		data |= LOONGSON_CFG1_MMI;
+	if (ases & MIPS_ASE_MSA)
+		data |= LOONGSON_CFG1_MSA1;
+
+	c->loongson3_cpucfg_data[0] = data;
+}
+
+static void patch_cpucfg_sel2(struct cpuinfo_mips *c)
+{
+	u64 ases = c->ases;
+	u64 options = c->options;
+	u32 data = c->loongson3_cpucfg_data[1];
+
+	if (ases & MIPS_ASE_LOONGSON_EXT)
+		data |= LOONGSON_CFG2_LEXT1;
+	if (ases & MIPS_ASE_LOONGSON_EXT2)
+		data |= LOONGSON_CFG2_LEXT2;
+	if (options & MIPS_CPU_LDPTE)
+		data |= LOONGSON_CFG2_LSPW;
+
+	if (ases & MIPS_ASE_VZ)
+		data |= LOONGSON_CFG2_LVZP;
+	else
+		data &= ~LOONGSON_CFG2_LVZREV;
+
+	c->loongson3_cpucfg_data[1] = data;
+}
+
+static void patch_cpucfg_sel3(struct cpuinfo_mips *c)
+{
+	u64 ases = c->ases;
+	u32 data = c->loongson3_cpucfg_data[2];
+
+	if (ases & MIPS_ASE_LOONGSON_CAM) {
+		data |= LOONGSON_CFG3_LCAMP;
+	} else {
+		data &= ~LOONGSON_CFG3_LCAMREV;
+		data &= ~LOONGSON_CFG3_LCAMNUM;
+		data &= ~LOONGSON_CFG3_LCAMKW;
+		data &= ~LOONGSON_CFG3_LCAMVW;
+	}
+
+	c->loongson3_cpucfg_data[2] = data;
+}
+
+void loongson3_cpucfg_synthesize_data(struct cpuinfo_mips *c)
+{
+	/* Only engage the logic on Loongson processors. */
+	if (!is_loongson(c))
+		return;
+
+	/* CPUs with CPUCFG support don't need to synthesize anything. */
+	if (cpu_has_cfg())
+		goto have_cpucfg_now;
+
+	c->loongson3_cpucfg_data[0] = 0;
+	c->loongson3_cpucfg_data[1] = 0;
+	c->loongson3_cpucfg_data[2] = 0;
+
+	/* Add CPUCFG features non-discoverable otherwise. */
+	switch (c->processor_id & (PRID_IMP_MASK | PRID_REV_MASK)) {
+	case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_0:
+	case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_1:
+	case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_2:
+	case PRID_IMP_LOONGSON_64R | PRID_REV_LOONGSON2K_R1_3:
+		decode_loongson_config6(c);
+		probe_uca(c);
+
+		c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
+			LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LLSYNC |
+			LOONGSON_CFG1_TGTSYNC);
+		c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
+			LOONGSON_CFG2_LBT2 | LOONGSON_CFG2_LPMP |
+			LOONGSON_CFG2_LPM_REV2);
+		c->loongson3_cpucfg_data[2] = 0;
+		break;
+
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R1:
+		c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
+			LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LSUCA |
+			LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
+		c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
+			LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1);
+		c->loongson3_cpucfg_data[2] |= (
+			LOONGSON_CFG3_LCAM_REV1 |
+			LOONGSON_CFG3_LCAMNUM_REV1 |
+			LOONGSON_CFG3_LCAMKW_REV1 |
+			LOONGSON_CFG3_LCAMVW_REV1);
+		break;
+
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R1:
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R2:
+		c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_LSLDR0 |
+			LOONGSON_CFG1_LSSYNCI | LOONGSON_CFG1_LSUCA |
+			LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
+		c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
+			LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1);
+		c->loongson3_cpucfg_data[2] |= (
+			LOONGSON_CFG3_LCAM_REV1 |
+			LOONGSON_CFG3_LCAMNUM_REV1 |
+			LOONGSON_CFG3_LCAMKW_REV1 |
+			LOONGSON_CFG3_LCAMVW_REV1);
+		break;
+
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_0:
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_1:
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R3_0:
+	case PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R3_1:
+		decode_loongson_config6(c);
+		probe_uca(c);
+
+		c->loongson3_cpucfg_data[0] |= (LOONGSON_CFG1_CNT64 |
+			LOONGSON_CFG1_LSLDR0 | LOONGSON_CFG1_LSPREF |
+			LOONGSON_CFG1_LSPREFX | LOONGSON_CFG1_LSSYNCI |
+			LOONGSON_CFG1_LLSYNC | LOONGSON_CFG1_TGTSYNC);
+		c->loongson3_cpucfg_data[1] |= (LOONGSON_CFG2_LBT1 |
+			LOONGSON_CFG2_LBT2 | LOONGSON_CFG2_LBTMMU |
+			LOONGSON_CFG2_LPMP | LOONGSON_CFG2_LPM_REV1 |
+			LOONGSON_CFG2_LVZ_REV1);
+		c->loongson3_cpucfg_data[2] |= (LOONGSON_CFG3_LCAM_REV1 |
+			LOONGSON_CFG3_LCAMNUM_REV1 |
+			LOONGSON_CFG3_LCAMKW_REV1 |
+			LOONGSON_CFG3_LCAMVW_REV1);
+		break;
+
+	default:
+		/* It is possible that some future Loongson cores still do
+		 * not have CPUCFG, so do not emulate anything for these
+		 * cores.
+		 */
+		return;
+	}
+
+	/* This feature is set by firmware, but all known Loongson-64 systems
+	 * are configured this way.
+	 */
+	c->loongson3_cpucfg_data[0] |= LOONGSON_CFG1_CDMAP;
+
+	/* Patch in dynamically probed bits. */
+	patch_cpucfg_sel1(c);
+	patch_cpucfg_sel2(c);
+	patch_cpucfg_sel3(c);
+
+have_cpucfg_now:
+	/* We have usable CPUCFG now, emulated or not.
+	 * Announce CPUCFG availability to userspace via hwcap.
+	 */
+	elf_hwcap |= HWCAP_LOONGSON_CPUCFG;
+}