[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20201020155922.GA27985@e121166-lin.cambridge.arm.com>
Date: Tue, 20 Oct 2020 16:59:22 +0100
From: Lorenzo Pieralisi <lorenzo.pieralisi@....com>
To: Vidya Sagar <vidyas@...dia.com>
Cc: jingoohan1@...il.com, gustavo.pimentel@...opsys.com,
bhelgaas@...gle.com, amurray@...goodpenguin.co.uk, robh@...nel.org,
treding@...dia.com, jonathanh@...dia.com,
linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
kthota@...dia.com, mmaddireddy@...dia.com, sagar.tv@...il.com
Subject: Re: [PATCH] PCI: dwc: Use ATU regions to map memory regions
On Mon, Oct 05, 2020 at 05:43:51PM +0530, Vidya Sagar wrote:
> Use ATU region-3 and region-0 to setup mapping for prefetchable and
> non-prefetchable memory regions respectively only if their respective CPU
> and bus addresses are different.
>
The commit subject and log must be rewritten. You should describe
why you are making this change, add a Link: tag to the discussion
we had about this change and provide a reason why we are making it.
Also, please add a Fixes: tag reference to the commit you are fixing.
I think this is related to prefetchable handling in DT and dwc/tegra,
we do need a link to those discussions here please.
> Signed-off-by: Vidya Sagar <vidyas@...dia.com>
> ---
> .../pci/controller/dwc/pcie-designware-host.c | 44 ++++++++++++++++---
> drivers/pci/controller/dwc/pcie-designware.c | 12 ++---
> drivers/pci/controller/dwc/pcie-designware.h | 4 +-
> 3 files changed, 48 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 317ff512f8df..cefde8e813e9 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -515,9 +515,40 @@ static struct pci_ops dw_pcie_ops = {
> .write = pci_generic_config_write,
> };
>
> +static void dw_pcie_setup_mem_atu(struct pcie_port *pp,
> + struct resource_entry *win)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> +
> + if (win->res->flags & IORESOURCE_PREFETCH && pci->num_viewport >= 4 &&
> + win->offset) {
> + dw_pcie_prog_outbound_atu(pci,
> + PCIE_ATU_REGION_INDEX3,
> + PCIE_ATU_TYPE_MEM,
> + win->res->start,
> + win->res->start - win->offset,
> + resource_size(win->res));
> + } else if (win->res->flags & IORESOURCE_PREFETCH &&
> + pci->num_viewport < 4) {
> + dev_warn(pci->dev,
> + "Insufficient ATU regions to map Prefetchable memory\n");
> + } else if (win->offset) {
> + if (upper_32_bits(resource_size(win->res)))
> + dev_warn(pci->dev,
> + "Memory resource size exceeds max for 32 bits\n");
> + dw_pcie_prog_outbound_atu(pci,
> + PCIE_ATU_REGION_INDEX0,
> + PCIE_ATU_TYPE_MEM,
> + win->res->start,
> + win->res->start - win->offset,
> + resource_size(win->res));
> + }
This function logic must be explained - anyone else reading it should
be able to understand it, I think it really deserves a comment.
> +}
> +
> void dw_pcie_setup_rc(struct pcie_port *pp)
> {
> u32 val, ctrl, num_ctrls;
> + struct resource_entry *win;
> struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>
> /*
> @@ -572,13 +603,14 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
> * ATU, so we should not program the ATU here.
> */
> if (pp->bridge->child_ops == &dw_child_pcie_ops) {
> - struct resource_entry *entry =
> - resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM);
> + resource_list_for_each_entry(win, &pp->bridge->windows) {
> + switch (resource_type(win->res)) {
> + case IORESOURCE_MEM:
> + dw_pcie_setup_mem_atu(pp, win);
> + break;
> + }
Nit: an if statement would do but that's not where the problem lies.
> + }
>
> - dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX0,
> - PCIE_ATU_TYPE_MEM, entry->res->start,
> - entry->res->start - entry->offset,
> - resource_size(entry->res));
> if (pci->num_viewport > 2)
> dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX2,
> PCIE_ATU_TYPE_IO, pp->io_base,
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index 3c1f17c78241..6033689abb15 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -227,7 +227,7 @@ static void dw_pcie_writel_ob_unroll(struct dw_pcie *pci, u32 index, u32 reg,
> static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
> int index, int type,
> u64 cpu_addr, u64 pci_addr,
> - u32 size)
> + u64 size)
> {
> u32 retries, val;
> u64 limit_addr = cpu_addr + size - 1;
> @@ -244,8 +244,10 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
> lower_32_bits(pci_addr));
> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
> upper_32_bits(pci_addr));
> - dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1,
> - type | PCIE_ATU_FUNC_NUM(func_no));
> + val = type | PCIE_ATU_FUNC_NUM(func_no);
> + val = upper_32_bits(size - 1) ?
> + val | PCIE_ATU_INCREASE_REGION_SIZE : val;
> + dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL2,
> PCIE_ATU_ENABLE);
>
> @@ -266,7 +268,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
>
> static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
> int index, int type, u64 cpu_addr,
> - u64 pci_addr, u32 size)
> + u64 pci_addr, u64 size)
> {
> u32 retries, val;
>
> @@ -310,7 +312,7 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
> }
>
> void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
> - u64 cpu_addr, u64 pci_addr, u32 size)
> + u64 cpu_addr, u64 pci_addr, u64 size)
> {
> __dw_pcie_prog_outbound_atu(pci, 0, index, type,
> cpu_addr, pci_addr, size);
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 97c7063b9e89..b81a1813cf9e 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -80,10 +80,12 @@
> #define PCIE_ATU_VIEWPORT 0x900
> #define PCIE_ATU_REGION_INBOUND BIT(31)
> #define PCIE_ATU_REGION_OUTBOUND 0
> +#define PCIE_ATU_REGION_INDEX3 0x3
> #define PCIE_ATU_REGION_INDEX2 0x2
> #define PCIE_ATU_REGION_INDEX1 0x1
> #define PCIE_ATU_REGION_INDEX0 0x0
> #define PCIE_ATU_CR1 0x904
> +#define PCIE_ATU_INCREASE_REGION_SIZE BIT(13)
> #define PCIE_ATU_TYPE_MEM 0x0
> #define PCIE_ATU_TYPE_IO 0x2
> #define PCIE_ATU_TYPE_CFG0 0x4
> @@ -295,7 +297,7 @@ void dw_pcie_upconfig_setup(struct dw_pcie *pci);
> int dw_pcie_wait_for_link(struct dw_pcie *pci);
> void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index,
> int type, u64 cpu_addr, u64 pci_addr,
> - u32 size);
> + u64 size);
> void dw_pcie_prog_ep_outbound_atu(struct dw_pcie *pci, u8 func_no, int index,
> int type, u64 cpu_addr, u64 pci_addr,
> u32 size);
> --
> 2.17.1
>
Powered by blists - more mailing lists