2019-08-07 07:53:57

by Benjamin Herrenschmidt

Subject: [PATCH v4 3/4] nvme-pci: Add support for Apple 2018+ models

Based on reverse engineering and original patch by

Paul Pawlowski <[email protected]>

This adds support for Apple weird implementation of NVME in their
2018 or later machines. It accounts for the twice-as-big SQ entries
for the IO queues, and the fact that only interrupt vector 0 appears
to function properly.

Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Reviewed-by: Minwoo Im <[email protected]>
---
drivers/nvme/host/nvme.h | 10 ++++++++++
drivers/nvme/host/pci.c | 21 ++++++++++++++++++++-
2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 8dc010ca30e5..0925f7fc13ff 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -92,6 +92,16 @@ enum nvme_quirks {
* Broken Write Zeroes.
*/
NVME_QUIRK_DISABLE_WRITE_ZEROES = (1 << 9),
+
+ /*
+ * Use only one interrupt vector for all queues
+ */
+ NVME_QUIRK_SINGLE_VECTOR = (1 << 10),
+
+ /*
+ * Use non-standard 128 bytes SQEs.
+ */
+ NVME_QUIRK_128_BYTES_SQES = (1 << 11),
};

/*
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 78a660e229d9..c683263cdf60 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2081,6 +2081,13 @@ static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues)
dev->io_queues[HCTX_TYPE_DEFAULT] = 1;
dev->io_queues[HCTX_TYPE_READ] = 0;

+ /*
+ * Some Apple controllers require all queues to use the
+ * first vector.
+ */
+ if (dev->ctrl.quirks & NVME_QUIRK_SINGLE_VECTOR)
+ irq_queues = 1;
+
return pci_alloc_irq_vectors_affinity(pdev, 1, irq_queues,
PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
}
@@ -2321,7 +2328,16 @@ static int nvme_pci_enable(struct nvme_dev *dev)
dev->ctrl.sqsize = dev->q_depth - 1; /* 0's based queue depth */
dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
dev->dbs = dev->bar + 4096;
- dev->io_sqes = NVME_NVM_IOSQES;
+
+ /*
+ * Some Apple controllers require a non-standard SQE size.
+ * Interestingly they also seem to ignore the CC:IOSQES register
+ * so we don't bother updating it here.
+ */
+ if (dev->ctrl.quirks & NVME_QUIRK_128_BYTES_SQES)
+ dev->io_sqes = 7;
+ else
+ dev->io_sqes = NVME_NVM_IOSQES;

/*
* Temporary fix for the Apple controller found in the MacBook8,1 and
@@ -3039,6 +3055,9 @@ static const struct pci_device_id nvme_id_table[] = {
{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
+ { PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2005),
+ .driver_data = NVME_QUIRK_SINGLE_VECTOR |
+ NVME_QUIRK_128_BYTES_SQES },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, nvme_id_table);
--
2.17.1

2019-08-22 05:41:48

by Christoph Hellwig

Subject: Re: [PATCH v4 3/4] nvme-pci: Add support for Apple 2018+ models

On Wed, Aug 07, 2019 at 05:51:21PM +1000, Benjamin Herrenschmidt wrote:
> Based on reverse engineering and original patch by
>
> Paul Pawlowski <[email protected]>
>
> This adds support for Apple weird implementation of NVME in their
> 2018 or later machines. It accounts for the twice-as-big SQ entries
> for the IO queues, and the fact that only interrupt vector 0 appears
> to function properly.
>
> Signed-off-by: Benjamin Herrenschmidt <[email protected]>
> Reviewed-by: Minwoo Im <[email protected]>

Looks good:

Reviewed-by: Christoph Hellwig <[email protected]>