linux-user: Add support for getting/setting RTC PLL correction using …

…ioctls

This patch implements functionalities of following ioctls:

RTC_PLL_GET - Getting PLL correction

    Read the PLL correction for RTCs that support PLL. The PLL correction
    is returned in the following structure:

        struct rtc_pll_info {
            int pll_ctrl;        /* placeholder for fancier control */
            int pll_value;       /* get/set correction value */
            int pll_max;         /* max +ve (faster) adjustment value */
            int pll_min;         /* max -ve (slower) adjustment value */
            int pll_posmult;     /* factor for +ve correction */
            int pll_negmult;     /* factor for -ve correction */
            long pll_clock;      /* base PLL frequency */
        };

    A pointer to this structure should be passed as the third
    ioctl's argument.

RTC_PLL_SET - Setting PLL correction

    Sets the PLL correction for RTCs that support PLL. The PLL correction
    that is set is specified by the rtc_pll_info structure pointed to by
    the third ioctl's' argument.

Implementation notes:

    All ioctls in this patch have a pointer to a structure rtc_pll_info
    as their third argument. All elements of this structure are of
    type 'int', except the last one that is of type 'long'. That is
    the reason why a separate target structure (target_rtc_pll_info)
    is defined in linux-user/syscall_defs. The rest of the
    implementation is straightforward.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Filip Bozuta <Filip.Bozuta@rt-rk.com>
Message-Id: <1579117007-7565-6-git-send-email-Filip.Bozuta@rt-rk.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

linux-user/ioctls.h

@@ -87,6 +87,8 @@
      IOCTL(RTC_EPOCH_SET, IOC_W, TYPE_ULONG)
      IOCTL(RTC_WKALM_RD, IOC_R, MK_PTR(MK_STRUCT(STRUCT_rtc_wkalrm)))
      IOCTL(RTC_WKALM_SET, IOC_W, MK_PTR(MK_STRUCT(STRUCT_rtc_wkalrm)))
+     IOCTL(RTC_PLL_GET, IOC_R, MK_PTR(MK_STRUCT(STRUCT_rtc_pll_info)))
+     IOCTL(RTC_PLL_SET, IOC_W, MK_PTR(MK_STRUCT(STRUCT_rtc_pll_info)))
 
      IOCTL(BLKROSET, IOC_W, MK_PTR(TYPE_INT))
      IOCTL(BLKROGET, IOC_R, MK_PTR(TYPE_INT))

linux-user/syscall_defs.h

@@ -763,6 +763,16 @@ struct target_pollfd {
 #define TARGET_KDSETLED        0x4B32	/* set led state [lights, not flags] */
 #define TARGET_KDSIGACCEPT     0x4B4E
 
+struct target_rtc_pll_info {
+    int pll_ctrl;
+    int pll_value;
+    int pll_max;
+    int pll_min;
+    int pll_posmult;
+    int pll_negmult;
+    abi_long pll_clock;
+};
+
 /* real time clock ioctls */
 #define TARGET_RTC_AIE_ON           TARGET_IO('p', 0x01)
 #define TARGET_RTC_AIE_OFF          TARGET_IO('p', 0x02)
@@ -782,6 +792,10 @@ struct target_pollfd {
 #define TARGET_RTC_EPOCH_SET        TARGET_IOW('p', 0x0e, abi_ulong)
 #define TARGET_RTC_WKALM_RD         TARGET_IOR('p', 0x10, struct rtc_wkalrm)
 #define TARGET_RTC_WKALM_SET        TARGET_IOW('p', 0x0f, struct rtc_wkalrm)
+#define TARGET_RTC_PLL_GET          TARGET_IOR('p', 0x11,                      \
+                                               struct target_rtc_pll_info)
+#define TARGET_RTC_PLL_SET          TARGET_IOW('p', 0x12,                      \
+                                               struct target_rtc_pll_info)
 
 #if defined(TARGET_ALPHA) || defined(TARGET_MIPS) || defined(TARGET_SH4) ||    \
        defined(TARGET_XTENSA)

linux-user/syscall_types.h

@@ -271,6 +271,15 @@ STRUCT(rtc_wkalrm,
        TYPE_CHAR, /* pending */
        MK_STRUCT(STRUCT_rtc_time)) /* time */
 
+STRUCT(rtc_pll_info,
+       TYPE_INT, /* pll_ctrl */
+       TYPE_INT, /* pll_value */
+       TYPE_INT, /* pll_max */
+       TYPE_INT, /* pll_min */
+       TYPE_INT, /* pll_posmult */
+       TYPE_INT, /* pll_negmult */
+       TYPE_LONG) /* pll_clock */
+
 STRUCT(blkpg_ioctl_arg,
        TYPE_INT, /* op */
        TYPE_INT, /* flags */