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authorSerge Semin <Sergey.Semin@baikalelectronics.ru>2022-06-24 17:39:44 +0300
committerBjorn Helgaas <bhelgaas@google.com>2022-08-01 23:15:32 +0300
commit89473aa9ab261948ed13b16effe841a675efed77 (patch)
tree615b9b547e60a073c23df5355c1a7acd0a262d8a /drivers/pci/controller/dwc/pcie-designware.c
parent5a163f5998185d3af58d825501765b08fd6ed32e (diff)
downloadlinux-89473aa9ab261948ed13b16effe841a675efed77.tar.xz
PCI: dwc: Add iATU regions size detection procedure
The DWC PCIe RC/EP/DM IP core configuration parameters determine the number of inbound and outbound iATU windows, alignment requirements (which is also the minimum window size), minimum and maximum sizes. If internal ATU is enabled, the former settings are determined by CX_ATU_MIN_REGION_SIZE; the latter are determined by CX_ATU_MAX_REGION_SIZE. Determine the required alignment and maximum size supported by the controller and log it to help verify whether the requested inbound or outbound memory mappings can be fully created. Note 1. The extended iATU regions have been supported since DWC PCIe v4.60a. There is no need in testing the upper limit register availability for the older cores. Note 2. The regions alignment is determined with using the fls() method since the lower four bits of the ATU Limit register can be occupied with the Circular Buffer Increment setting, which can be initialized with zeros. Link: https://lore.kernel.org/r/20220624143947.8991-13-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-designware.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-designware.c33
1 files changed, 29 insertions, 4 deletions
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 6ddda710d6de..cb6244db9269 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -8,9 +8,11 @@
* Author: Jingoo Han <jg1.han@samsung.com>
*/
+#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_platform.h>
+#include <linux/sizes.h>
#include <linux/types.h>
#include "../../pci.h"
@@ -522,7 +524,8 @@ static bool dw_pcie_iatu_unroll_enabled(struct dw_pcie *pci)
static void dw_pcie_iatu_detect_regions(struct dw_pcie *pci)
{
int max_region, ob, ib;
- u32 val;
+ u32 val, min, dir;
+ u64 max;
if (pci->iatu_unroll_enabled) {
max_region = min((int)pci->atu_size / 512, 256);
@@ -545,8 +548,29 @@ static void dw_pcie_iatu_detect_regions(struct dw_pcie *pci)
break;
}
- pci->num_ib_windows = ib;
+ if (ob) {
+ dir = PCIE_ATU_REGION_DIR_OB;
+ } else if (ib) {
+ dir = PCIE_ATU_REGION_DIR_IB;
+ } else {
+ dev_err(pci->dev, "No iATU regions found\n");
+ return;
+ }
+
+ dw_pcie_writel_atu(pci, dir, 0, PCIE_ATU_LIMIT, 0x0);
+ min = dw_pcie_readl_atu(pci, dir, 0, PCIE_ATU_LIMIT);
+
+ if (dw_pcie_ver_is_ge(pci, 460A)) {
+ dw_pcie_writel_atu(pci, dir, 0, PCIE_ATU_UPPER_LIMIT, 0xFFFFFFFF);
+ max = dw_pcie_readl_atu(pci, dir, 0, PCIE_ATU_UPPER_LIMIT);
+ } else {
+ max = 0;
+ }
+
pci->num_ob_windows = ob;
+ pci->num_ib_windows = ib;
+ pci->region_align = 1 << fls(min);
+ pci->region_limit = (max << 32) | (SZ_4G - 1);
}
void dw_pcie_iatu_detect(struct dw_pcie *pci)
@@ -579,8 +603,9 @@ void dw_pcie_iatu_detect(struct dw_pcie *pci)
dev_info(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
"enabled" : "disabled");
- dev_info(pci->dev, "Detected iATU regions: %u outbound, %u inbound\n",
- pci->num_ob_windows, pci->num_ib_windows);
+ dev_info(pci->dev, "iATU regions: %u ob, %u ib, align %uK, limit %lluG\n",
+ pci->num_ob_windows, pci->num_ib_windows,
+ pci->region_align / SZ_1K, (pci->region_limit + 1) / SZ_1G);
}
void dw_pcie_setup(struct dw_pcie *pci)