2
0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-09-04 20:19:47 +08:00

iommu/riscv: Add shutdown function for iommu driver

This commit supplies shutdown callback for iommu driver. The shutdown
callback resets necessary registers so that newly booted kernel can pass
riscv_iommu_init_check() after kexec. Also, the shutdown callback resets
iommu mode to bare instead of off so that new kernel can still use PCIE
devices even when CONFIG_RISCV_IOMMU is not enabled.

Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Link: https://lore.kernel.org/r/20250103093220.38106-3-luxu.kernel@bytedance.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Xu Lu 2025-01-03 17:32:20 +08:00 committed by Joerg Roedel
parent 8d8d3752c0
commit 77a44196ab
4 changed files with 19 additions and 2 deletions

View File

@ -101,6 +101,13 @@ static void riscv_iommu_pci_remove(struct pci_dev *pdev)
riscv_iommu_remove(iommu);
}
static void riscv_iommu_pci_shutdown(struct pci_dev *pdev)
{
struct riscv_iommu_device *iommu = dev_get_drvdata(&pdev->dev);
riscv_iommu_disable(iommu);
}
static const struct pci_device_id riscv_iommu_pci_tbl[] = {
{PCI_VDEVICE(REDHAT, PCI_DEVICE_ID_REDHAT_RISCV_IOMMU), 0},
{PCI_VDEVICE(RIVOS, PCI_DEVICE_ID_RIVOS_RISCV_IOMMU_GA), 0},
@ -112,6 +119,7 @@ static struct pci_driver riscv_iommu_pci_driver = {
.id_table = riscv_iommu_pci_tbl,
.probe = riscv_iommu_pci_probe,
.remove = riscv_iommu_pci_remove,
.shutdown = riscv_iommu_pci_shutdown,
.driver = {
.suppress_bind_attrs = true,
},

View File

@ -140,6 +140,11 @@ static void riscv_iommu_platform_remove(struct platform_device *pdev)
platform_device_msi_free_irqs_all(&pdev->dev);
};
static void riscv_iommu_platform_shutdown(struct platform_device *pdev)
{
riscv_iommu_disable(dev_get_drvdata(&pdev->dev));
};
static const struct of_device_id riscv_iommu_of_match[] = {
{.compatible = "riscv,iommu",},
{},
@ -148,6 +153,7 @@ static const struct of_device_id riscv_iommu_of_match[] = {
static struct platform_driver riscv_iommu_platform_driver = {
.probe = riscv_iommu_platform_probe,
.remove = riscv_iommu_platform_remove,
.shutdown = riscv_iommu_platform_shutdown,
.driver = {
.name = "riscv,iommu",
.of_match_table = riscv_iommu_of_match,

View File

@ -651,9 +651,11 @@ static struct riscv_iommu_dc *riscv_iommu_get_dc(struct riscv_iommu_device *iomm
* This is best effort IOMMU translation shutdown flow.
* Disable IOMMU without waiting for hardware response.
*/
static void riscv_iommu_disable(struct riscv_iommu_device *iommu)
void riscv_iommu_disable(struct riscv_iommu_device *iommu)
{
riscv_iommu_writeq(iommu, RISCV_IOMMU_REG_DDTP, 0);
riscv_iommu_writeq(iommu, RISCV_IOMMU_REG_DDTP,
FIELD_PREP(RISCV_IOMMU_DDTP_IOMMU_MODE,
RISCV_IOMMU_DDTP_IOMMU_MODE_BARE));
riscv_iommu_writel(iommu, RISCV_IOMMU_REG_CQCSR, 0);
riscv_iommu_writel(iommu, RISCV_IOMMU_REG_FQCSR, 0);
riscv_iommu_writel(iommu, RISCV_IOMMU_REG_PQCSR, 0);

View File

@ -64,6 +64,7 @@ struct riscv_iommu_device {
int riscv_iommu_init(struct riscv_iommu_device *iommu);
void riscv_iommu_remove(struct riscv_iommu_device *iommu);
void riscv_iommu_disable(struct riscv_iommu_device *iommu);
#define riscv_iommu_readl(iommu, addr) \
readl_relaxed((iommu)->reg + (addr))