From 5be10f349bc0a2f3dd2ab6417ffe29746403984c Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 17 Jan 2013 10:03:01 +0200 Subject: [PATCH] dw_dmac: don't exceed AHB master number in dwc_get_data_width The driver assumes that hardware has two AHB masters which might not be always true. In such cases we must not exceed number of the AHB masters present in the hardware. In the proposed scheme in this patch, we would choose the master with highest possible number whenever we exceed max AHB masters. Signed-off-by: Andy Shevchenko Acked-by: Viresh Kumar Signed-off-by: Vinod Koul --- drivers/dma/dw_dmac.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index 76301c4ba1ad..635a4a5d31ae 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -47,13 +47,29 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave) return slave ? slave->src_master : 1; } +#define SRC_MASTER 0 +#define DST_MASTER 1 + +static inline unsigned int dwc_get_master(struct dma_chan *chan, int master) +{ + struct dw_dma *dw = to_dw_dma(chan->device); + struct dw_dma_slave *dws = chan->private; + unsigned int m; + + if (master == SRC_MASTER) + m = dwc_get_sms(dws); + else + m = dwc_get_dms(dws); + + return min_t(unsigned int, dw->nr_masters - 1, m); +} + #define DWC_DEFAULT_CTLLO(_chan) ({ \ - struct dw_dma_slave *__slave = (_chan->private); \ struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan); \ struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \ bool _is_slave = is_slave_direction(_dwc->direction); \ - int _dms = dwc_get_dms(__slave); \ - int _sms = dwc_get_sms(__slave); \ + int _dms = dwc_get_master(_chan, DST_MASTER); \ + int _sms = dwc_get_master(_chan, SRC_MASTER); \ u8 _smsize = _is_slave ? _sconfig->src_maxburst : \ DW_DMA_MSIZE_16; \ u8 _dmsize = _is_slave ? _sconfig->dst_maxburst : \ @@ -74,20 +90,11 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave) */ #define NR_DESCS_PER_CHANNEL 64 -#define SRC_MASTER 0 -#define DST_MASTER 1 - static inline unsigned int dwc_get_data_width(struct dma_chan *chan, int master) { struct dw_dma *dw = to_dw_dma(chan->device); - struct dw_dma_slave *dws = chan->private; - - if (master == SRC_MASTER) - return dw->data_width[dwc_get_sms(dws)]; - else if (master == DST_MASTER) - return dw->data_width[dwc_get_dms(dws)]; - return 0; + return dw->data_width[dwc_get_master(chan, master)]; } /*----------------------------------------------------------------------*/ -- 2.34.1