[PATCH 1/4] MIPS: uaccess: emulate Ingenic LXW/LXH/LXHU uaccess

[PATCH 1/4] MIPS: uaccess: emulate Ingenic LXW/LXH/LXHU uaccess

[Paul Cercueil]

From: Siarhei Volkau <lis8215@gmail.com>

The LXW, LXH, LXHU opcodes are part of the MXU ASE found in Ingenic
XBurst based SoCs.

While technically part of the MXU ASE, they do not touch any of the SIMD
registers, and can be used even when the MXU ASE is disabled.

This patch makes it possible to emulate unaligned access for those
instructions.

Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
---
 arch/mips/include/uapi/asm/inst.h | 33 +++++++++++++++++++++++++
 arch/mips/kernel/unaligned.c      | 41 +++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+)

diff --git a/arch/mips/include/uapi/asm/inst.h b/arch/mips/include/uapi/asm/inst.h
index 43d1faa02933..c29dbc8c1d49 100644
--- a/arch/mips/include/uapi/asm/inst.h
+++ b/arch/mips/include/uapi/asm/inst.h
@@ -272,6 +272,27 @@ enum lx_func {
 	lbx_op	= 0x16,
 };
 
+/*
+ * func field for special2 MXU opcodes (Ingenic XBurst MXU).
+ */
+enum mxu_func {
+	/* TODO, other MXU funcs */
+	mxu_lx_op = 0x28,
+};
+
+/*
+ * op field for special2 MXU LX opcodes (Ingenic XBurst MXU).
+ */
+enum lx_ingenic_func {
+	mxu_lxb_op,
+	mxu_lxh_op,
+	/* reserved */
+	mxu_lxw_op = 3,
+	mxu_lxbu_op,
+	mxu_lxhu_op,
+	/* more reserved */
+};
+
 /*
  * BSHFL opcodes
  */
@@ -774,6 +795,17 @@ struct dsp_format {		/* SPEC3 DSP format instructions */
 	;))))))
 };
 
+struct mxu_lx_format {		/* SPEC2 MXU LX format instructions */
+	__BITFIELD_FIELD(unsigned int opcode : 6,
+	__BITFIELD_FIELD(unsigned int rs : 5,
+	__BITFIELD_FIELD(unsigned int rt : 5,
+	__BITFIELD_FIELD(unsigned int rd : 5,
+	__BITFIELD_FIELD(unsigned int strd : 2,
+	__BITFIELD_FIELD(unsigned int op : 3,
+	__BITFIELD_FIELD(unsigned int func : 6,
+	;)))))))
+};
+
 struct spec3_format {   /* SPEC3 */
 	__BITFIELD_FIELD(unsigned int opcode:6,
 	__BITFIELD_FIELD(unsigned int rs:5,
@@ -1125,6 +1157,7 @@ union mips_instruction {
 	struct loongson3_lswc2_format loongson3_lswc2_format;
 	struct loongson3_lsdc2_format loongson3_lsdc2_format;
 	struct loongson3_lscsr_format loongson3_lscsr_format;
+	struct mxu_lx_format mxu_lx_format;
 };
 
 union mips16e_instruction {
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index 7b5aba5df02e..f4cf94e92ec3 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -160,6 +160,47 @@ static void emulate_load_store_insn(struct pt_regs *regs,
 		 * The remaining opcodes are the ones that are really of
 		 * interest.
 		 */
+#ifdef CONFIG_MACH_INGENIC
+	case spec2_op:
+		if (insn.mxu_lx_format.func != mxu_lx_op)
+			goto sigbus; /* other MXU instructions we don't care */
+
+		switch (insn.mxu_lx_format.op) {
+		case mxu_lxw_op:
+			if (user && !access_ok(addr, 4))
+				goto sigbus;
+			LoadW(addr, value, res);
+			if (res)
+				goto fault;
+			compute_return_epc(regs);
+			regs->regs[insn.mxu_lx_format.rd] = value;
+			break;
+		case mxu_lxh_op:
+			if (user && !access_ok(addr, 2))
+				goto sigbus;
+			LoadHW(addr, value, res);
+			if (res)
+				goto fault;
+			compute_return_epc(regs);
+			regs->regs[insn.dsp_format.rd] = value;
+			break;
+		case mxu_lxhu_op:
+			if (user && !access_ok(addr, 2))
+				goto sigbus;
+			LoadHWU(addr, value, res);
+			if (res)
+				goto fault;
+			compute_return_epc(regs);
+			regs->regs[insn.dsp_format.rd] = value;
+			break;
+		case mxu_lxb_op:
+		case mxu_lxbu_op:
+			goto sigbus;
+		default:
+			goto sigill;
+		}
+		break;
+#endif
 	case spec3_op:
 		if (insn.dsp_format.func == lx_op) {
 			switch (insn.dsp_format.op) {
-- 
2.39.2

[PATCH 2/4] mips: ingenic: Remove useless __maybe_unused

[Paul Cercueil]

These flags are useless in this case as the code referencing these data
structures is always seen by the compiler (and not behind #ifdef
guards).

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
 arch/mips/generic/board-ingenic.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/generic/board-ingenic.c b/arch/mips/generic/board-ingenic.c
index c422bbc890ed..7a4fce06875d 100644
--- a/arch/mips/generic/board-ingenic.c
+++ b/arch/mips/generic/board-ingenic.c
@@ -117,14 +117,14 @@ static void ingenic_halt(void)
 		ingenic_wait_instr();
 }
 
-static int __maybe_unused ingenic_pm_enter(suspend_state_t state)
+static int ingenic_pm_enter(suspend_state_t state)
 {
 	ingenic_wait_instr();
 
 	return 0;
 }
 
-static const struct platform_suspend_ops ingenic_pm_ops __maybe_unused = {
+static const struct platform_suspend_ops ingenic_pm_ops = {
 	.valid = suspend_valid_only_mem,
 	.enter = ingenic_pm_enter,
 };
-- 
2.39.2

[PATCH 3/4] mips: ingenic: Enable EXT/2 divider on JZ4750/55/60 if EXT is 24 MHz

[Paul Cercueil]

The JZ4750, JZ4755 and JZ4760 (non-B version) support using a 24 MHz
external crystal oscillator instead of the typical 12 MHz one.

However, most of the SoC's IP blocks only work with a 12 MHz clock.
Thanksfully, there is a /2 divider we can enable when a 24 MHz external
crystal is present.

Force-enable this /2 divider when the oscillator is 24 MHz, so that the
SoC always uses a 12 MHz clock internally.

It is done here, and not in the clocks driver, because we need the EXT
clock to be 12 MHz for the early console to work, and the clocks driver
probes way too late.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
 arch/mips/generic/board-ingenic.c | 57 +++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/arch/mips/generic/board-ingenic.c b/arch/mips/generic/board-ingenic.c
index 7a4fce06875d..1f4906875e7b 100644
--- a/arch/mips/generic/board-ingenic.c
+++ b/arch/mips/generic/board-ingenic.c
@@ -17,6 +17,7 @@
 #include <linux/types.h>
 
 #include <asm/bootinfo.h>
+#include <asm/io.h>
 #include <asm/machine.h>
 #include <asm/reboot.h>
 
@@ -60,6 +61,50 @@ static __init char *ingenic_get_system_type(unsigned long machtype)
 	}
 }
 
+#define INGENIC_CGU_BASE	0x10000000
+#define JZ4750_CGU_CPCCR_ECS	BIT(30)
+#define JZ4760_CGU_CPCCR_ECS	BIT(31)
+
+static __init void ingenic_force_12M_ext(const void *fdt, unsigned int mask)
+{
+	const __be32 *prop;
+	unsigned int cpccr;
+	void __iomem *cgu;
+	bool use_div;
+	int offset;
+
+	offset = fdt_path_offset(fdt, "/ext");
+	if (offset < 0)
+		return;
+
+	prop = fdt_getprop(fdt, offset, "clock-frequency", NULL);
+	if (!prop)
+		return;
+
+	/*
+	 * If the external oscillator is 24 MHz, enable the /2 divider to
+	 * drive it down to 12 MHz, since this is what the hardware can work
+	 * with.
+	 * The 16 MHz cutoff value is arbitrary; setting it to 12 MHz would not
+	 * work as the crystal frequency (as reported in the Device Tree) might
+	 * be slightly above this value.
+	 */
+	use_div = be32_to_cpup(prop) >= 16000000;
+
+	cgu = ioremap(INGENIC_CGU_BASE, 0x4);
+	if (!cgu)
+		return;
+
+	cpccr = ioread32(cgu);
+	if (use_div)
+		cpccr |= mask;
+	else
+		cpccr &= ~mask;
+	iowrite32(cpccr, cgu);
+
+	iounmap(cgu);
+}
+
 static __init const void *ingenic_fixup_fdt(const void *fdt, const void *match_data)
 {
 	/*
@@ -73,6 +118,18 @@ static __init const void *ingenic_fixup_fdt(const void *fdt, const void *match_d
 	mips_machtype = (unsigned long)match_data;
 	system_type = ingenic_get_system_type(mips_machtype);
 
+	switch (mips_machtype) {
+	case MACH_INGENIC_JZ4750:
+	case MACH_INGENIC_JZ4755:
+		ingenic_force_12M_ext(fdt, JZ4750_CGU_CPCCR_ECS);
+		break;
+	case MACH_INGENIC_JZ4760:
+		ingenic_force_12M_ext(fdt, JZ4760_CGU_CPCCR_ECS);
+		break;
+	default:
+		break;
+	}
+
 	return fdt;
 }
 
-- 
2.39.2

[PATCH 4/4] MIPS: DTS: qi_lb60: Don't use unit address for regulators

[Paul Cercueil]

The regulators don't have any "reg" property, and therefore shouldn't
use an unit address in their node names.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: devicetree@vger.kernel.org
---
 arch/mips/boot/dts/ingenic/qi_lb60.dts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/mips/boot/dts/ingenic/qi_lb60.dts b/arch/mips/boot/dts/ingenic/qi_lb60.dts
index ba0218971572..24f987244a12 100644
--- a/arch/mips/boot/dts/ingenic/qi_lb60.dts
+++ b/arch/mips/boot/dts/ingenic/qi_lb60.dts
@@ -27,7 +27,7 @@ chosen {
 		stdout-path = &uart0;
 	};
 
-	vcc: regulator@0 {
+	vcc: regulator-0 {
 		compatible = "regulator-fixed";
 		regulator-name = "vcc";
 
@@ -36,7 +36,7 @@ vcc: regulator@0 {
 		regulator-always-on;
 	};
 
-	mmc_power: regulator@1 {
+	mmc_power: regulator-1 {
 		compatible = "regulator-fixed";
 		regulator-name = "mmc_vcc";
 		gpio = <&gpd 2 0>;
@@ -45,7 +45,7 @@ mmc_power: regulator@1 {
 		regulator-max-microvolt = <3300000>;
 	};
 
-	amp_supply: regulator@2 {
+	amp_supply: regulator-2 {
 		compatible = "regulator-fixed";
 		regulator-name = "amp_supply";
 		gpio = <&gpd 4 0>;
-- 
2.39.2

Re: [PATCH 1/4] MIPS: uaccess: emulate Ingenic LXW/LXH/LXHU uaccess

[Thomas Bogendoerfer]

On Sun, Jun 04, 2023 at 02:26:52PM +0200, Paul Cercueil wrote:
> From: Siarhei Volkau <lis8215@gmail.com>
> 
> The LXW, LXH, LXHU opcodes are part of the MXU ASE found in Ingenic
> XBurst based SoCs.
> 
> While technically part of the MXU ASE, they do not touch any of the SIMD
> registers, and can be used even when the MXU ASE is disabled.
> 
> This patch makes it possible to emulate unaligned access for those
> instructions.
> 
> Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
> ---
>  arch/mips/include/uapi/asm/inst.h | 33 +++++++++++++++++++++++++
>  arch/mips/kernel/unaligned.c      | 41 +++++++++++++++++++++++++++++++
>  2 files changed, 74 insertions(+)

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]

Re: [PATCH 2/4] mips: ingenic: Remove useless __maybe_unused

[Thomas Bogendoerfer]

On Sun, Jun 04, 2023 at 02:26:53PM +0200, Paul Cercueil wrote:
> These flags are useless in this case as the code referencing these data
> structures is always seen by the compiler (and not behind #ifdef
> guards).
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> ---
>  arch/mips/generic/board-ingenic.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/mips/generic/board-ingenic.c b/arch/mips/generic/board-ingenic.c
> index c422bbc890ed..7a4fce06875d 100644
> --- a/arch/mips/generic/board-ingenic.c
> +++ b/arch/mips/generic/board-ingenic.c
> @@ -117,14 +117,14 @@ static void ingenic_halt(void)
>  		ingenic_wait_instr();
>  }
>  
> -static int __maybe_unused ingenic_pm_enter(suspend_state_t state)
> +static int ingenic_pm_enter(suspend_state_t state)
>  {
>  	ingenic_wait_instr();
>  
>  	return 0;
>  }
>  
> -static const struct platform_suspend_ops ingenic_pm_ops __maybe_unused = {
> +static const struct platform_suspend_ops ingenic_pm_ops = {
>  	.valid = suspend_valid_only_mem,
>  	.enter = ingenic_pm_enter,
>  };
> -- 
> 2.39.2

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]

Re: [PATCH 3/4] mips: ingenic: Enable EXT/2 divider on JZ4750/55/60 if EXT is 24 MHz

[Thomas Bogendoerfer]

On Sun, Jun 04, 2023 at 02:26:54PM +0200, Paul Cercueil wrote:
> The JZ4750, JZ4755 and JZ4760 (non-B version) support using a 24 MHz
> external crystal oscillator instead of the typical 12 MHz one.
> 
> However, most of the SoC's IP blocks only work with a 12 MHz clock.
> Thanksfully, there is a /2 divider we can enable when a 24 MHz external
> crystal is present.
> 
> Force-enable this /2 divider when the oscillator is 24 MHz, so that the
> SoC always uses a 12 MHz clock internally.
> 
> It is done here, and not in the clocks driver, because we need the EXT
> clock to be 12 MHz for the early console to work, and the clocks driver
> probes way too late.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> ---
>  arch/mips/generic/board-ingenic.c | 57 +++++++++++++++++++++++++++++++
>  1 file changed, 57 insertions(+)

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]

Re: [PATCH 4/4] MIPS: DTS: qi_lb60: Don't use unit address for regulators

[Thomas Bogendoerfer]

On Sun, Jun 04, 2023 at 02:26:55PM +0200, Paul Cercueil wrote:
> The regulators don't have any "reg" property, and therefore shouldn't
> use an unit address in their node names.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> ---
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: devicetree@vger.kernel.org
> ---
>  arch/mips/boot/dts/ingenic/qi_lb60.dts | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]