summaryrefslogtreecommitdiffstats
path: root/drivers/staging/most/hdm-dim2
diff options
context:
space:
mode:
authorChristian Gromm <christian.gromm@microchip.com>2016-08-18 16:58:46 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-08-18 17:24:00 +0200
commit9fe7aeaca7ffec24a821c493b272614bd153b9aa (patch)
tree83186d59ba39e6f3e796e046cda9bc234cecccab /drivers/staging/most/hdm-dim2
parent8dfb8fdbd2d1dd4facef6eef24a26b6bc1b33191 (diff)
downloadlinux-9fe7aeaca7ffec24a821c493b272614bd153b9aa.tar.bz2
staging: most: dim2-hdm: initialize DBR memory of synchronous channels
In the time after a synchronous DIM2 channel is enabled and before the first buffer travels this channel, the DIM2 macro is babbling random random data to the network. This patch initializes the internal DBR memory of the DIM2 that is used to transfer the synchronous data. Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de> Signed-off-by: Christian Gromm <christian.gromm@microchip.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/most/hdm-dim2')
-rw-r--r--drivers/staging/most/hdm-dim2/dim2_hal.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/staging/most/hdm-dim2/dim2_hal.c b/drivers/staging/most/hdm-dim2/dim2_hal.c
index a0b935c72671..901f742f2fd7 100644
--- a/drivers/staging/most/hdm-dim2/dim2_hal.c
+++ b/drivers/staging/most/hdm-dim2/dim2_hal.c
@@ -135,6 +135,27 @@ static void free_dbr(int offs, int size)
/* -------------------------------------------------------------------------- */
+static void dim2_clear_dbr(u16 addr, u16 size)
+{
+ enum { MADR_TB_BIT = 30, MADR_WNR_BIT = 31 };
+
+ u16 const end_addr = addr + size;
+ u32 const cmd = bit_mask(MADR_WNR_BIT) | bit_mask(MADR_TB_BIT);
+
+ dimcb_io_write(&g.dim2->MCTL, 0); /* clear transfer complete */
+ dimcb_io_write(&g.dim2->MDAT0, 0);
+
+ for (; addr < end_addr; addr++) {
+ dimcb_io_write(&g.dim2->MADR, cmd | addr);
+
+ /* wait till transfer is completed */
+ while ((dimcb_io_read(&g.dim2->MCTL) & 1) != 1)
+ continue;
+
+ dimcb_io_write(&g.dim2->MCTL, 0); /* clear transfer complete */
+ }
+}
+
static u32 dim2_read_ctr(u32 ctr_addr, u16 mdat_idx)
{
dimcb_io_write(&g.dim2->MADR, ctr_addr);
@@ -794,6 +815,7 @@ u8 dim_init_sync(struct dim_channel *ch, u8 is_tx, u16 ch_address,
sync_init(ch, ch_address / 2, bytes_per_frame);
+ dim2_clear_dbr(ch->dbr_addr, ch->dbr_size);
dim2_configure_channel(ch->addr, CAT_CT_VAL_SYNC, is_tx,
ch->dbr_addr, ch->dbr_size, 0, true);