kernel.git/drivers/net/ipa/gsi.c, branch linux-5.14.y

net: ipa: introduce gsi_ring_setup()

2021-06-21T19:30:59Z

Prior to IPA v3.5.1, there is no HW_PARAM_2 GSI register, which we use to determine the number of channels and endpoints per execution environment. In that case, we will just assume the number supported is the maximum supported by the driver. Introduce gsi_ring_setup() to encapsulate the code that determines the number of channels and endpoints. Update GSI_EVT_RING_COUNT_MAX so it is big enough to handle any available channel for all supported hardware (IPA v4.9 can have 23 channels and 24 event rings). Signed-off-by: Alex Elder Acked-by: AngeloGioacchino Del Regno Signed-off-by: David S. Miller

net: ipa: inter-EE interrupts aren't always available

2021-06-21T19:30:59Z

The GSI inter-EE interrupts are not supported prior to IPA v3.5. Don't attempt to initialize them in gsi_irq_setup() for hardware that does not support them. Originally proposed by AngeloGioacchino Del Regno. Link: https://lore.kernel.org/netdev/20210211175015.200772-4-angelogioacchino.delregno@somainline.org Signed-off-by: Alex Elder Acked-by: AngeloGioacchino Del Regno Signed-off-by: David S. Miller

net: ipa: fix inter-EE IRQ register definitions

2021-05-06T23:32:10Z

In gsi_irq_setup(), two registers are written with the intention of disabling inter-EE channel and event IRQs. But the wrong registers are used (and defined); the ones used are read-only registers that indicate whether the interrupt condition is present. Define the mask registers instead of the status registers, and use them to disable the inter-EE interrupt types. Fixes: 46f748ccaf01 ("net: ipa: explicitly disallow inter-EE interrupts") Signed-off-by: Alex Elder Link: https://lore.kernel.org/r/20210505223636.232527-1-elder@linaro.org Signed-off-by: Jakub Kicinski

net: ipa: get rid of empty GSI functions

2021-04-10T03:57:25Z

There are place holder functions in the GSI code that do nothing. Remove these, knowing we can add something back in their place if they're really needed someday. Some of these are inverse functions (such as teardown to match setup). Explicitly comment that there is no inverse in these cases. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: DMA addresses are nicely aligned

2021-03-29T01:12:03Z

A recent patch avoided doing 64-bit modulo operations by checking the alignment of some DMA allocations using only the lower 32 bits of the address. David Laight pointed out (after the fix was committed) that DMA allocations might already satisfy the alignment requirements. And he was right. Remove the alignment checks that occur after DMA allocation requests, and update comments to explain why the constraint is satisfied. The only place IPA_TABLE_ALIGN was used was to check the alignment; it is therefore no longer needed, so get rid of it. Add comments where GSI_RING_ELEMENT_SIZE and the tre_count and event_count channel data fields are defined to make explicit they are required to be powers of 2. Revise a comment in gsi_trans_pool_init_dma(), taking into account that dma_alloc_coherent() guarantees its result is aligned to a page size (or order thereof). Don't bother printing an error if a DMA allocation fails. Suggested-by: David Laight Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: expand GSI channel types

2021-03-26T00:22:30Z

IPA v4.5 (GSI v2.5) supports a larger set of channel protocols, and adds an additional field to hold the most-significant bits of the protocol identifier on a channel. Add an inline function that encodes the protocol (including the extra bits for newer versions of IPA), and define some additional protocols. At this point we still use only GPI protocol. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: update GSI ring size registers

2021-03-26T00:22:30Z

Each GSI channel has a CNTXT_1 register that encodes the size of its ring buffer. The size of the field that records that is increased starting at IPA v4.9. Replace the use of a fixed-size field mask with a new inline function that encodes that size value. Similarly, the size of GSI event rings can be larger starting with IPA v4.9, so create a function to encode that as well. Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: reduce IPA version assumptions

2021-03-24T23:52:47Z

Modify conditional tests throughout the IPA code so they do not assume that IPA v3.5.1 is the oldest version supported. Also remove assumptions that IPA v4.5 is the newest version of IPA supported. Augment versions in comments with "+", to be clearer that the comment applies to a version and subsequent versions. (E.g., "present for IPA v4.2+" instead of just "present for v4.2".) Signed-off-by: Alex Elder Signed-off-by: David S. Miller

net: ipa: avoid 64-bit modulus

2021-03-24T00:15:23Z

It is possible for a 32 bit x86 build to use a 64 bit DMA address. There are two remaining spots where the IPA driver does a modulo operation to check alignment of a DMA address, and under certain conditions this can lead to a build error on i386 (at least). The alignment checks we're doing are for power-of-2 values, and this means the lower 32 bits of the DMA address can be used. This ensures both operands to the modulo operator are 32 bits wide. Reported-by: Randy Dunlap Signed-off-by: Alex Elder Acked-by: Randy Dunlap # build-tested Signed-off-by: David S. Miller

net: ipa: use upper_32_bits()

2021-03-18T23:20:34Z

Use upper_32_bits() to extract the high-order 32 bits of a DMA address. This avoids doing a 32-position shift on a DMA address if it happens not to be 64 bits wide. Use lower_32_bits() to extract the low-order 32 bits (because that's what it's for). Suggested-by: Florian Fainelli Signed-off-by: Alex Elder Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller