On Tue, Dec 22, 2009 at 12:08 AM, Roman Fietze
<roman.fie...@telemotive.de> wrote:
>
> Signed-off-by: Roman Fietze <roman.fie...@telemotive.de>
> ---
> arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c | 33
> +++++++++++++++----------
> 1 files changed, 20 insertions(+), 13 deletions(-)
>
> diff --git a/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
> b/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
> index 48f2b4f..21b2a40 100644
> --- a/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
> +++ b/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
> @@ -80,11 +80,11 @@ static inline int mpc52xx_lpbfifo_is_poll_dma(int flags)
> */
> static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
> {
> - size_t transfer_size = req->size - req->pos;
> + size_t tc = req->size - req->pos;
> struct bcom_bd *bd;
> void __iomem *reg;
> u32 *data;
> - u32 bit_fields;
> + u32 control;
Changing the name of these two variables makes it hard to review the
functional change. A lot of unrelated housekeeping gets interwoven.
> int rflags = req->flags;
>
> /* Set and clear the reset bits; is good practice in User Manual */
> @@ -93,10 +93,10 @@ static void mpc52xx_lpbfifo_kick(struct
> mpc52xx_lpbfifo_request *req)
> /* Set width, chip select and READ mode */
> out_be32(&lpbfifo.regs->start_address, req->offset + req->pos);
>
> - /* Set CS and BPT */
> - bit_fields = MPC52xx_SCLPC_CONTROL_CS(req->cs) | 0x8;
> + /* Setup CS */
> + control = MPC52xx_SCLPC_CONTROL_CS(req->cs);
> if (!(mpc52xx_lpbfifo_is_write(rflags)))
> - bit_fields |= MPC52xx_SCLPC_CONTROL_RWB_RECEIVE; /*
> read mode */
> + control |= MPC52xx_SCLPC_CONTROL_RWB_RECEIVE; /* read mode
> */
>
> if (!mpc52xx_lpbfifo_is_dma(rflags)) {
> /* While the FIFO can be setup for transfer sizes as
> @@ -112,10 +112,10 @@ static void mpc52xx_lpbfifo_kick(struct
> mpc52xx_lpbfifo_request *req)
> * The last block of data will be received with the
> * flush bit set. This avoids stale read data.
> */
> - if (transfer_size > 512)
> - transfer_size = 512;
> + if (tc > 512)
> + tc = 512;
> else if (!(mpc52xx_lpbfifo_is_write(rflags)))
> - bit_fields |= MPC52xx_SCLPC_CONTROL_FLUSH;
> + control |= MPC52xx_SCLPC_CONTROL_FLUSH;
>
> /* Load the FIFO with data */
> if (mpc52xx_lpbfifo_is_write(rflags)) {
> @@ -123,7 +123,7 @@ static void mpc52xx_lpbfifo_kick(struct
> mpc52xx_lpbfifo_request *req)
>
> reg = &lpbfifo.regs->fifo_data;
> data = req->data + req->pos;
> - for (i = 0; i < transfer_size; i += 4)
> + for (i = 0; i < tc; i += 4)
> out_be32(reg, *data++);
> }
>
> @@ -136,7 +136,7 @@ static void mpc52xx_lpbfifo_kick(struct
> mpc52xx_lpbfifo_request *req)
> /* In DMA mode we can always set the flush bit to avoid
> * stale read data. */
> if (!(mpc52xx_lpbfifo_is_write(rflags)))
> - bit_fields |= MPC52xx_SCLPC_CONTROL_FLUSH;
> + control |= MPC52xx_SCLPC_CONTROL_FLUSH;
>
> /* Choose the correct direction
> *
> @@ -173,15 +173,17 @@ static void mpc52xx_lpbfifo_kick(struct
> mpc52xx_lpbfifo_request *req)
> out_be32(&lpbfifo.regs->enable, MPC52xx_SCLPC_ENABLE_AIE |
> MPC52xx_SCLPC_ENABLE_NIE | MPC52xx_SCLPC_ENABLE_ME);
>
> bd = bcom_prepare_next_buffer(lpbfifo.bcom_cur_task);
> - bd->status = transfer_size;
> + bd->status = tc;
> bd->data[0] = req->data_dma + req->pos;
> bcom_submit_next_buffer(lpbfifo.bcom_cur_task, NULL);
> }
>
> - out_be32(&lpbfifo.regs->control, bit_fields);
> + /* Setup BPT. tc is already screened and a multiple of 4 */
> + control |= tc & 7 ? 4 : 8;
> + out_be32(&lpbfifo.regs->control, control);
The calculation looks correct. However, why isn't the transfer size
calculated up by the /* Setup CS and BPT */ comment? I don't think it
needs to be down here.
>
> /* Set packet size and kick it off */
> - out_be32(&lpbfifo.regs->packet_size.packet_size,
> MPC52xx_SCLPC_PACKET_SIZE_RESTART | transfer_size);
> + out_be32(&lpbfifo.regs->packet_size.packet_size,
> MPC52xx_SCLPC_PACKET_SIZE_RESTART | tc);
> if (mpc52xx_lpbfifo_is_dma(rflags))
> bcom_enable(lpbfifo.bcom_cur_task);
> }
> @@ -395,6 +397,11 @@ int mpc52xx_lpbfifo_submit(struct
> mpc52xx_lpbfifo_request *req)
> if (!lpbfifo.regs)
> return -ENODEV;
>
> + /* The gen bd BestComm task currently only allows an increment
> + * of 4 */
> + if (!req->size || req->size & 0x03)
> + return -EINVAL;
> +
> spin_lock_irqsave(&lpbfifo.lock, flags);
>
> /* If the req pointer is already set, then a transfer is in progress */
> --
> 1.6.5.5
>
>
>
> --
> Roman Fietze Telemotive AG Büro Mühlhausen
> Breitwiesen 73347 Mühlhausen
> Tel.: +49(0)7335/18493-45 http://www.telemotive.de
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
>
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
