Commit 77a44196 authored by Xu Lu's avatar Xu Lu Committed by Joerg Roedel
Browse files

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: default avatarXu Lu <luxu.kernel@bytedance.com>
Link: https://lore.kernel.org/r/20250103093220.38106-3-luxu.kernel@bytedance.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 8d8d3752

drivers/iommu/riscv/iommu-pci.c

+8 −0
Original line number Diff line number Diff line
@@ -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,

	},

drivers/iommu/riscv/iommu-platform.c

+6 −0
Original line number Diff line number Diff line
@@ -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,

drivers/iommu/riscv/iommu.c

+4 −2
Original line number Diff line number Diff line
@@ -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);

drivers/iommu/riscv/iommu.h

+1 −0
Original line number Diff line number Diff line
@@ -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))