diff mbox series

[RFC,v1,07/10] clocksource: clint: Add support for ACLINT MTIMER device

Message ID 20210612160422.330705-8-anup.patel@wdc.com
State New
Headers show
Series RISC-V ACLINT Support | expand

Commit Message

Anup Patel June 12, 2021, 4:04 p.m. UTC
The RISC-V ACLINT specification is a modular specification and the
ACLINT MTIMER device is compatible with the M-mode timer functionality
of the CLINT device. This patch extends the CLINT driver to support
both CLINT device and ACLINT MTIMER device.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
 drivers/clocksource/timer-clint.c | 43 +++++++++++++++++++++----------
 1 file changed, 30 insertions(+), 13 deletions(-)

Comments

Bin Meng June 14, 2021, 1:34 p.m. UTC | #1
On Sun, Jun 13, 2021 at 12:07 AM Anup Patel <anup.patel@wdc.com> wrote:
>

> The RISC-V ACLINT specification is a modular specification and the

> ACLINT MTIMER device is compatible with the M-mode timer functionality

> of the CLINT device. This patch extends the CLINT driver to support

> both CLINT device and ACLINT MTIMER device.

>

> Signed-off-by: Anup Patel <anup.patel@wdc.com>

> ---

>  drivers/clocksource/timer-clint.c | 43 +++++++++++++++++++++----------

>  1 file changed, 30 insertions(+), 13 deletions(-)

>

> diff --git a/drivers/clocksource/timer-clint.c b/drivers/clocksource/timer-clint.c

> index dfdcd94c1fd5..ca329c450810 100644

> --- a/drivers/clocksource/timer-clint.c

> +++ b/drivers/clocksource/timer-clint.c

> @@ -2,8 +2,15 @@

>  /*

>   * Copyright (C) 2020 Western Digital Corporation or its affiliates.

>   *

> - * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a

> - * CLINT MMIO timer device.

> + * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a CLINT

> + * MMIO device which is a composite device capable of injecting M-mode

> + * software interrupts and M-mode timer interrupts.

> + *

> + * The RISC-V ACLINT specification is modular in nature and defines

> + * separate devices for M-mode software interrupt (MSWI), M-mode timer

> + * (MTIMER) and S-mode software interrupt (SSWI).

> + *

> + * This is a common driver for CLINT device and ACLINT MTIMER device.

>   */

>

>  #define pr_fmt(fmt) "clint: " fmt

> @@ -21,14 +28,20 @@

>  #include <linux/smp.h>

>  #include <linux/timex.h>

>

> -#ifndef CONFIG_RISCV_M_MODE

> +#ifdef CONFIG_RISCV_M_MODE

>  #include <asm/clint.h>

> +

> +u64 __iomem *clint_time_val;

> +EXPORT_SYMBOL(clint_time_val);

>  #endif

>

>  #define CLINT_IPI_OFF          0

>  #define CLINT_TIMER_CMP_OFF    0x4000

>  #define CLINT_TIMER_VAL_OFF    0xbff8

>

> +#define ACLINT_MTIMER_CMP_OFF  0x0000

> +#define ACLINT_MTIMER_VAL_OFF  0x7ff8

> +

>  /* CLINT manages IPI and Timer for RISC-V M-mode  */

>  static u32 __iomem *clint_ipi_base;

>  static u64 __iomem *clint_timer_cmp;

> @@ -36,11 +49,6 @@ static u64 __iomem *clint_timer_val;

>  static unsigned long clint_timer_freq;

>  static unsigned int clint_timer_irq;

>

> -#ifdef CONFIG_RISCV_M_MODE

> -u64 __iomem *clint_time_val;

> -EXPORT_SYMBOL(clint_time_val);

> -#endif

> -

>  static void clint_send_ipi(const struct cpumask *target)

>  {

>         unsigned int cpu;

> @@ -191,9 +199,15 @@ static int __init clint_timer_init_dt(struct device_node *np)

>                 return -ENODEV;

>         }

>

> -       clint_ipi_base = base + CLINT_IPI_OFF;

> -       clint_timer_cmp = base + CLINT_TIMER_CMP_OFF;

> -       clint_timer_val = base + CLINT_TIMER_VAL_OFF;

> +       if (of_device_is_compatible(np, "riscv,aclint-mtimer")) {


This patch should come after patch 8 which introduces this DT binding

> +               clint_ipi_base = NULL;

> +               clint_timer_cmp = base + ACLINT_MTIMER_CMP_OFF;

> +               clint_timer_val = base + ACLINT_MTIMER_VAL_OFF;

> +       } else {

> +               clint_ipi_base = base + CLINT_IPI_OFF;

> +               clint_timer_cmp = base + CLINT_TIMER_CMP_OFF;

> +               clint_timer_val = base + CLINT_TIMER_VAL_OFF;

> +       }

>         clint_timer_freq = riscv_timebase;

>

>  #ifdef CONFIG_RISCV_M_MODE

> @@ -230,8 +244,10 @@ static int __init clint_timer_init_dt(struct device_node *np)

>                 goto fail_free_irq;

>         }

>

> -       riscv_set_ipi_ops(&clint_ipi_ops);

> -       clint_clear_ipi();

> +       if (clint_ipi_base) {

> +               riscv_set_ipi_ops(&clint_ipi_ops);

> +               clint_clear_ipi();

> +       }

>

>         return 0;

>

> @@ -244,3 +260,4 @@ static int __init clint_timer_init_dt(struct device_node *np)

>

>  TIMER_OF_DECLARE(clint_timer, "riscv,clint0", clint_timer_init_dt);

>  TIMER_OF_DECLARE(clint_timer1, "sifive,clint0", clint_timer_init_dt);

> +TIMER_OF_DECLARE(clint_timer2, "riscv,aclint-mtimer", clint_timer_init_dt);


Otherwise,
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff mbox series

Patch

diff --git a/drivers/clocksource/timer-clint.c b/drivers/clocksource/timer-clint.c
index dfdcd94c1fd5..ca329c450810 100644
--- a/drivers/clocksource/timer-clint.c
+++ b/drivers/clocksource/timer-clint.c
@@ -2,8 +2,15 @@ 
 /*
  * Copyright (C) 2020 Western Digital Corporation or its affiliates.
  *
- * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a
- * CLINT MMIO timer device.
+ * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a CLINT
+ * MMIO device which is a composite device capable of injecting M-mode
+ * software interrupts and M-mode timer interrupts.
+ *
+ * The RISC-V ACLINT specification is modular in nature and defines
+ * separate devices for M-mode software interrupt (MSWI), M-mode timer
+ * (MTIMER) and S-mode software interrupt (SSWI).
+ *
+ * This is a common driver for CLINT device and ACLINT MTIMER device.
  */
 
 #define pr_fmt(fmt) "clint: " fmt
@@ -21,14 +28,20 @@ 
 #include <linux/smp.h>
 #include <linux/timex.h>
 
-#ifndef CONFIG_RISCV_M_MODE
+#ifdef CONFIG_RISCV_M_MODE
 #include <asm/clint.h>
+
+u64 __iomem *clint_time_val;
+EXPORT_SYMBOL(clint_time_val);
 #endif
 
 #define CLINT_IPI_OFF		0
 #define CLINT_TIMER_CMP_OFF	0x4000
 #define CLINT_TIMER_VAL_OFF	0xbff8
 
+#define ACLINT_MTIMER_CMP_OFF	0x0000
+#define ACLINT_MTIMER_VAL_OFF	0x7ff8
+
 /* CLINT manages IPI and Timer for RISC-V M-mode  */
 static u32 __iomem *clint_ipi_base;
 static u64 __iomem *clint_timer_cmp;
@@ -36,11 +49,6 @@  static u64 __iomem *clint_timer_val;
 static unsigned long clint_timer_freq;
 static unsigned int clint_timer_irq;
 
-#ifdef CONFIG_RISCV_M_MODE
-u64 __iomem *clint_time_val;
-EXPORT_SYMBOL(clint_time_val);
-#endif
-
 static void clint_send_ipi(const struct cpumask *target)
 {
 	unsigned int cpu;
@@ -191,9 +199,15 @@  static int __init clint_timer_init_dt(struct device_node *np)
 		return -ENODEV;
 	}
 
-	clint_ipi_base = base + CLINT_IPI_OFF;
-	clint_timer_cmp = base + CLINT_TIMER_CMP_OFF;
-	clint_timer_val = base + CLINT_TIMER_VAL_OFF;
+	if (of_device_is_compatible(np, "riscv,aclint-mtimer")) {
+		clint_ipi_base = NULL;
+		clint_timer_cmp = base + ACLINT_MTIMER_CMP_OFF;
+		clint_timer_val = base + ACLINT_MTIMER_VAL_OFF;
+	} else {
+		clint_ipi_base = base + CLINT_IPI_OFF;
+		clint_timer_cmp = base + CLINT_TIMER_CMP_OFF;
+		clint_timer_val = base + CLINT_TIMER_VAL_OFF;
+	}
 	clint_timer_freq = riscv_timebase;
 
 #ifdef CONFIG_RISCV_M_MODE
@@ -230,8 +244,10 @@  static int __init clint_timer_init_dt(struct device_node *np)
 		goto fail_free_irq;
 	}
 
-	riscv_set_ipi_ops(&clint_ipi_ops);
-	clint_clear_ipi();
+	if (clint_ipi_base) {
+		riscv_set_ipi_ops(&clint_ipi_ops);
+		clint_clear_ipi();
+	}
 
 	return 0;
 
@@ -244,3 +260,4 @@  static int __init clint_timer_init_dt(struct device_node *np)
 
 TIMER_OF_DECLARE(clint_timer, "riscv,clint0", clint_timer_init_dt);
 TIMER_OF_DECLARE(clint_timer1, "sifive,clint0", clint_timer_init_dt);
+TIMER_OF_DECLARE(clint_timer2, "riscv,aclint-mtimer", clint_timer_init_dt);