From aa59d6bb5ec88e30802174f9accc5d2dc50209ad Mon Sep 17 00:00:00 2001 From: Even Xu Date: Thu, 10 Jun 2021 14:21:54 +0800 Subject: HID: intel-ish-hid: ipc: Specify that EHL no cache snooping Specify that EHL doesn't support DMA cache snooping. Acked-by: Pandruvada, Srinivas Signed-off-by: Even Xu Signed-off-by: Jiri Kosina --- drivers/hid/intel-ish-hid/ipc/ipc.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) (limited to 'drivers/hid/intel-ish-hid') diff --git a/drivers/hid/intel-ish-hid/ipc/ipc.c b/drivers/hid/intel-ish-hid/ipc/ipc.c index 9037816e2bf7..45e0c7b1c9ec 100644 --- a/drivers/hid/intel-ish-hid/ipc/ipc.c +++ b/drivers/hid/intel-ish-hid/ipc/ipc.c @@ -889,6 +889,29 @@ static uint32_t ish_ipc_get_header(struct ishtp_device *dev, int length, return drbl_val; } +/** + * _dma_no_cache_snooping() + * + * Check on current platform, DMA supports cache snooping or not. + * This callback is used to notify uplayer driver if manully cache + * flush is needed when do DMA operation. + * + * Please pay attention to this callback implementation, if declare + * having cache snooping on a cache snooping not supported platform + * will cause uplayer driver receiving mismatched data; and if + * declare no cache snooping on a cache snooping supported platform + * will cause cache be flushed twice and performance hit. + * + * @dev: ishtp device pointer + * + * Return: false - has cache snooping capability + * true - no cache snooping, need manually cache flush + */ +static bool _dma_no_cache_snooping(struct ishtp_device *dev) +{ + return dev->pdev->device == EHL_Ax_DEVICE_ID; +} + static const struct ishtp_hw_ops ish_hw_ops = { .hw_reset = _ish_hw_reset, .ipc_reset = _ish_ipc_reset, @@ -897,7 +920,8 @@ static const struct ishtp_hw_ops ish_hw_ops = { .write = write_ipc_to_queue, .get_fw_status = _ish_read_fw_sts_reg, .sync_fw_clock = _ish_sync_fw_clock, - .ishtp_read_hdr = _ishtp_read_hdr + .ishtp_read_hdr = _ishtp_read_hdr, + .dma_no_cache_snooping = _dma_no_cache_snooping }; /** -- cgit v1.2.3