1ddi_iomin(9F) Kernel Functions for Drivers ddi_iomin(9F)
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6 ddi_iomin - find minimum alignment and transfer size for DMA
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9 #include <sys/conf.h>
10 #include <sys/ddi.h>
11 #include <sys/sunddi.h>
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15 int ddi_iomin(dev_info_t *dip, int initial, int streaming);
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19 Solaris DDI specific (Solaris DDI). This interface is obsolete.
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22 dip A pointer to the device's dev_info structure.
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25 initial The initial minimum DMAtransfer size in bytes. This may be
26 zero or an appropriate dlim_minxfer value for device's
27 ddi_dma_lim structure (see ddi_dma_lim_sparc(9S) or
28 ddi_dma_lim_x86(9S)). This value must be a power of two.
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31 streaming This argument, if non-zero, indicates that the returned
32 value should be modified to account for streaming mode
33 accesses (see ddi_dma_req(9S) for a discussion of stream‐
34 ing versus non-streaming access mode).
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38 The ddi_iomin() function, finds out the minimum DMAtransfer size for
39 the device pointed to by dip. This provides a mechanism by which a
40 driver can determine the effects of underlying caches as well as inter‐
41 vening bus adapters on the granularity of a DMA transfer.
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44 The ddi_iomin() function returns the minimum DMAtransfer size for the
45 calling device, or it returns zero, which means that you cannot get
46 there from here.
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49 This function can be called from user, interrupt, or kernel context.
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52 See attributes(5) for descriptions of the following attributes:
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57 ┌─────────────────────────────┬─────────────────────────────┐
58 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
59 ├─────────────────────────────┼─────────────────────────────┤
60 │Interface Stability │Obsolete │
61 └─────────────────────────────┴─────────────────────────────┘
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64 ddi_dma_devalign(9F), ddi_dma_setup(9F), ddi_dma_sync(9F),
65 ddi_dma_lim_sparc(9S), ddi_dma_lim_x86(9S), ddi_dma_req(9S)
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68 Writing Device Drivers
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72SunOS 5.11 04 Apr 2006 ddi_iomin(9F)