Re: [PATCH 1/4] powerpc/powernv: remove the unused pnv_pci_set_p2p function

From: CÃdric Le Goater
Date: Tue Jun 25 2019 - 06:55:29 EST

Hello Christoph,

On 25/06/2019 10:15, Christoph Hellwig wrote:
> This function has never been used anywhere in the kernel tree since it
> was added to the tree. We also now have proper PCIe P2P APIs in the core
> kernel, and any new P2P support should be using those.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> arch/powerpc/include/asm/opal.h | 7 --
> arch/powerpc/include/asm/pnv-pci.h | 2 -
> arch/powerpc/platforms/powernv/opal-call.c | 1 -
> arch/powerpc/platforms/powernv/pci.c | 74 ----------------------
> arch/powerpc/platforms/powernv/pci.h | 5 --
> 5 files changed, 89 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
> index 4cc37e708bc7..7b0bc104a89c 100644
> --- a/arch/powerpc/include/asm/opal.h
> +++ b/arch/powerpc/include/asm/opal.h
> @@ -280,13 +280,6 @@ int64_t opal_xive_allocate_irq(uint32_t chip_id);
> int64_t opal_xive_free_irq(uint32_t girq);
> int64_t opal_xive_sync(uint32_t type, uint32_t id);
> int64_t opal_xive_dump(uint32_t type, uint32_t id);
> -int64_t opal_xive_get_queue_state(uint64_t vp, uint32_t prio,
> - __be32 *out_qtoggle,
> - __be32 *out_qindex);
> -int64_t opal_xive_set_queue_state(uint64_t vp, uint32_t prio,
> - uint32_t qtoggle,
> - uint32_t qindex);
> -int64_t opal_xive_get_vp_state(uint64_t vp, __be64 *out_w01);


This hunk seems unrelated.

These OPAL calls are new. They are used by the XIVE KVM device
to get/set the interrupt controller state of a guest.


> int64_t opal_pci_set_p2p(uint64_t phb_init, uint64_t phb_target,
> uint64_t desc, uint16_t pe_number);

I suppose this is the one ^ you wanted to remove.

Cheers,

C.



>
> diff --git a/arch/powerpc/include/asm/pnv-pci.h b/arch/powerpc/include/asm/pnv-pci.h
> index 630eb8b1b7ed..9fcb0bc462c6 100644
> --- a/arch/powerpc/include/asm/pnv-pci.h
> +++ b/arch/powerpc/include/asm/pnv-pci.h
> @@ -26,8 +26,6 @@ extern int pnv_pci_get_presence_state(uint64_t id, uint8_t *state);
> extern int pnv_pci_get_power_state(uint64_t id, uint8_t *state);
> extern int pnv_pci_set_power_state(uint64_t id, uint8_t state,
> struct opal_msg *msg);
> -extern int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target,
> - u64 desc);
>
> extern int pnv_pci_enable_tunnel(struct pci_dev *dev, uint64_t *asnind);
> extern int pnv_pci_disable_tunnel(struct pci_dev *dev);
> diff --git a/arch/powerpc/platforms/powernv/opal-call.c b/arch/powerpc/platforms/powernv/opal-call.c
> index 36c8fa3647a2..29ca523c1c79 100644
> --- a/arch/powerpc/platforms/powernv/opal-call.c
> +++ b/arch/powerpc/platforms/powernv/opal-call.c
> @@ -273,7 +273,6 @@ OPAL_CALL(opal_npu_map_lpar, OPAL_NPU_MAP_LPAR);
> OPAL_CALL(opal_imc_counters_init, OPAL_IMC_COUNTERS_INIT);
> OPAL_CALL(opal_imc_counters_start, OPAL_IMC_COUNTERS_START);
> OPAL_CALL(opal_imc_counters_stop, OPAL_IMC_COUNTERS_STOP);
> -OPAL_CALL(opal_pci_set_p2p, OPAL_PCI_SET_P2P);
> OPAL_CALL(opal_get_powercap, OPAL_GET_POWERCAP);
> OPAL_CALL(opal_set_powercap, OPAL_SET_POWERCAP);
> OPAL_CALL(opal_get_power_shift_ratio, OPAL_GET_POWER_SHIFT_RATIO);
> diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
> index ef9448a907c6..8d28f2932c3b 100644
> --- a/arch/powerpc/platforms/powernv/pci.c
> +++ b/arch/powerpc/platforms/powernv/pci.c
> @@ -38,7 +38,6 @@
> #include "powernv.h"
> #include "pci.h"
>
> -static DEFINE_MUTEX(p2p_mutex);
> static DEFINE_MUTEX(tunnel_mutex);
>
> int pnv_pci_get_slot_id(struct device_node *np, uint64_t *id)
> @@ -861,79 +860,6 @@ void pnv_pci_dma_bus_setup(struct pci_bus *bus)
> }
> }
>
> -int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target, u64 desc)
> -{
> - struct pci_controller *hose;
> - struct pnv_phb *phb_init, *phb_target;
> - struct pnv_ioda_pe *pe_init;
> - int rc;
> -
> - if (!opal_check_token(OPAL_PCI_SET_P2P))
> - return -ENXIO;
> -
> - hose = pci_bus_to_host(initiator->bus);
> - phb_init = hose->private_data;
> -
> - hose = pci_bus_to_host(target->bus);
> - phb_target = hose->private_data;
> -
> - pe_init = pnv_ioda_get_pe(initiator);
> - if (!pe_init)
> - return -ENODEV;
> -
> - /*
> - * Configuring the initiator's PHB requires to adjust its
> - * TVE#1 setting. Since the same device can be an initiator
> - * several times for different target devices, we need to keep
> - * a reference count to know when we can restore the default
> - * bypass setting on its TVE#1 when disabling. Opal is not
> - * tracking PE states, so we add a reference count on the PE
> - * in linux.
> - *
> - * For the target, the configuration is per PHB, so we keep a
> - * target reference count on the PHB.
> - */
> - mutex_lock(&p2p_mutex);
> -
> - if (desc & OPAL_PCI_P2P_ENABLE) {
> - /* always go to opal to validate the configuration */
> - rc = opal_pci_set_p2p(phb_init->opal_id, phb_target->opal_id,
> - desc, pe_init->pe_number);
> -
> - if (rc != OPAL_SUCCESS) {
> - rc = -EIO;
> - goto out;
> - }
> -
> - pe_init->p2p_initiator_count++;
> - phb_target->p2p_target_count++;
> - } else {
> - if (!pe_init->p2p_initiator_count ||
> - !phb_target->p2p_target_count) {
> - rc = -EINVAL;
> - goto out;
> - }
> -
> - if (--pe_init->p2p_initiator_count == 0)
> - pnv_pci_ioda2_set_bypass(pe_init, true);
> -
> - if (--phb_target->p2p_target_count == 0) {
> - rc = opal_pci_set_p2p(phb_init->opal_id,
> - phb_target->opal_id, desc,
> - pe_init->pe_number);
> - if (rc != OPAL_SUCCESS) {
> - rc = -EIO;
> - goto out;
> - }
> - }
> - }
> - rc = 0;
> -out:
> - mutex_unlock(&p2p_mutex);
> - return rc;
> -}
> -EXPORT_SYMBOL_GPL(pnv_pci_set_p2p);
> -
> struct device_node *pnv_pci_get_phb_node(struct pci_dev *dev)
> {
> struct pci_controller *hose = pci_bus_to_host(dev->bus);
> diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
> index be26ab3d99e0..4f11c077af62 100644
> --- a/arch/powerpc/platforms/powernv/pci.h
> +++ b/arch/powerpc/platforms/powernv/pci.h
> @@ -79,9 +79,6 @@ struct pnv_ioda_pe {
> struct pnv_ioda_pe *master;
> struct list_head slaves;
>
> - /* PCI peer-to-peer*/
> - int p2p_initiator_count;
> -
> /* Link in list of PE#s */
> struct list_head list;
> };
> @@ -172,8 +169,6 @@ struct pnv_phb {
> /* PHB and hub diagnostics */
> unsigned int diag_data_size;
> u8 *diag_data;
> -
> - int p2p_target_count;
> };
>
> extern struct pci_ops pnv_pci_ops;
>