Signed-off-by: Matthieu Castet <[email protected]>
---
drivers/tty/hvc/hvc_dcc.c | 83 +++++++++++++++++++++++++++++++++++++++++----
1 file changed, 76 insertions(+), 7 deletions(-)
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
index 44fbeba..5f8827f 100644
--- a/drivers/tty/hvc/hvc_dcc.c
+++ b/drivers/tty/hvc/hvc_dcc.c
@@ -27,10 +27,10 @@
#include "hvc_console.h"
/* DCC Status Bits */
-#define DCC_STATUS_RX (1 << 30)
-#define DCC_STATUS_TX (1 << 29)
+#define DCC_STATUS_RX_V6 (1 << 30)
+#define DCC_STATUS_TX_V6 (1 << 29)
-static inline u32 __dcc_getstatus(void)
+static inline u32 __dcc_getstatus_v6(void)
{
u32 __ret;
asm volatile("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
@@ -40,7 +40,7 @@ static inline u32 __dcc_getstatus(void)
}
-static inline char __dcc_getchar(void)
+static inline char __dcc_getchar_v6(void)
{
char __c;
@@ -51,7 +51,7 @@ static inline char __dcc_getchar(void)
return __c;
}
-static inline void __dcc_putchar(char c)
+static inline void __dcc_putchar_v6(char c)
{
asm volatile("mcr p14, 0, %0, c0, c5, 0 @ write a char"
: /* no output register */
@@ -59,6 +59,69 @@ static inline void __dcc_putchar(char c)
isb();
}
+static int hvc_dcc_put_chars_v6(uint32_t vt, const char *buf, int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ while (__dcc_getstatus_v6() & DCC_STATUS_TX_V6)
+ cpu_relax();
+
+ __dcc_putchar_v6(buf[i]);
+ }
+
+ return count;
+}
+
+static int hvc_dcc_get_chars_v6(uint32_t vt, char *buf, int count)
+{
+ int i;
+
+ for (i = 0; i < count; ++i)
+ if (__dcc_getstatus_v6() & DCC_STATUS_RX_V6)
+ buf[i] = __dcc_getchar_v6();
+ else
+ break;
+
+ return i;
+}
+
+static const struct hv_ops hvc_dcc_get_put_ops_v6 = {
+ .get_chars = hvc_dcc_get_chars_v6,
+ .put_chars = hvc_dcc_put_chars_v6,
+};
+
+#define DCC_STATUS_RX (1 << 0)
+#define DCC_STATUS_TX (1 << 1)
+
+/* primitive JTAG1 protocol utilities */
+static inline u32 __dcc_getstatus(void)
+{
+ u32 ret;
+
+ asm __volatile__ ("mrc p14, 0, %0, c0, c0 @ read comms ctrl reg"
+ : "=r" (ret));
+
+ return ret;
+}
+
+static inline char __dcc_getchar(void)
+{
+ char c;
+
+ asm __volatile__ ("mrc p14, 0, %0, c1, c0 @ read comms data reg"
+ : "=r" (c));
+
+ return c;
+}
+
+static inline void __dcc_putchar(unsigned char c)
+{
+ asm __volatile__ ("mcr p14, 0, %0, c1, c0 @ write a char"
+ : /* no output register */
+ : "r" (c));
+}
+
static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
{
int i;
@@ -93,14 +156,20 @@ static const struct hv_ops hvc_dcc_get_put_ops = {
static int __init hvc_dcc_console_init(void)
{
- hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
+ if (cpu_architecture() >= CPU_ARCH_ARMv6)
+ hvc_instantiate(0, 0, &hvc_dcc_get_put_ops_v6);
+ else
+ hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
return 0;
}
console_initcall(hvc_dcc_console_init);
static int __init hvc_dcc_init(void)
{
- hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
+ if (cpu_architecture() >= CPU_ARCH_ARMv6)
+ hvc_alloc(0, 0, &hvc_dcc_get_put_ops_v6, 128);
+ else
+ hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
return 0;
}
device_initcall(hvc_dcc_init);
--
1.7.10.4
On 8/31/2012 4:47 AM, Matthieu CASTET wrote:
> Signed-off-by: Matthieu Castet <[email protected]>
Please consider adding some sort of commit text. Does this add some new
feature I may want on some downstream distro kernel?
> @@ -51,7 +51,7 @@ static inline char __dcc_getchar(void)
> return __c;
> }
>
> -static inline void __dcc_putchar(char c)
> +static inline void __dcc_putchar_v6(char c)
> {
> asm volatile("mcr p14, 0, %0, c0, c5, 0 @ write a char"
> : /* no output register */
> @@ -59,6 +59,69 @@ static inline void __dcc_putchar(char c)
> isb();
> }
>
> +static int hvc_dcc_put_chars_v6(uint32_t vt, const char *buf, int count)
> +{
> + int i;
> +
> + for (i = 0; i < count; i++) {
> + while (__dcc_getstatus_v6() & DCC_STATUS_TX_V6)
> + cpu_relax();
> +
> + __dcc_putchar_v6(buf[i]);
> + }
> +
> + return count;
> +}
It's unfortunate that the main logic is duplicated. I wonder if we could
push the runtime decision slightly lower into the accessor functions
instead and make some new functions dcc_tx_busy() and dcc_rx_busy() or
something. Then these loops stay the same.
> +
> +static int hvc_dcc_get_chars_v6(uint32_t vt, char *buf, int count)
> +{
> + int i;
> +
> + for (i = 0; i < count; ++i)
> + if (__dcc_getstatus_v6() & DCC_STATUS_RX_V6)
> + buf[i] = __dcc_getchar_v6();
> + else
> + break;
> +
> + return i;
> +}
> +
> +static const struct hv_ops hvc_dcc_get_put_ops_v6 = {
> + .get_chars = hvc_dcc_get_chars_v6,
> + .put_chars = hvc_dcc_put_chars_v6,
> +};
> +
> +#define DCC_STATUS_RX (1 << 0)
> +#define DCC_STATUS_TX (1 << 1)
> +
> +/* primitive JTAG1 protocol utilities */
This comment doesn't tell me much. Remove it?
> +static inline u32 __dcc_getstatus(void)
> +{
> + u32 ret;
> +
> + asm __volatile__ ("mrc p14, 0, %0, c0, c0 @ read comms ctrl reg"
> + : "=r" (ret));
Can you use volatile instead of __volatile__ so that the file is consistent?
> +
> + return ret;
> +}
> +
> +static inline char __dcc_getchar(void)
> +{
> + char c;
> +
> + asm __volatile__ ("mrc p14, 0, %0, c1, c0 @ read comms data reg"
> + : "=r" (c));
> +
Do you see any multiple character inputs? I think you may need an isb
here similar to the v6/7 code and in the putchar as well.
> + return c;
> +}
> +
> +static inline void __dcc_putchar(unsigned char c)
> +{
> + asm __volatile__ ("mcr p14, 0, %0, c1, c0 @ write a char"
> + : /* no output register */
> + : "r" (c));
> +}
> +
> static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
> {
> int i;
>
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.