From ed12f295bfd5c378970106891f12999589aec4e5 Mon Sep 17 00:00:00 2001 From: Kuppuswamy Sathyanarayanan Date: Fri, 15 Nov 2013 16:21:54 -0800 Subject: [PATCH] ipc: Added support for IPC interrupt mode This patch adds support for ipc command interrupt mode. Also added platform data option to select 'irq_mode' irq_mode = 1: configure the driver to receive IOC interrupt for each successful ipc_command. irq_mode = 0: makes driver use polling method to track the command completion status. Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: David Cohen Signed-off-by: Matthew Garrett --- drivers/platform/x86/intel_scu_ipc.c | 48 ++++++++++++++++++++++++++-- 1 file changed, 45 insertions(+), 3 deletions(-) diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c index e26830f6c8dd..60ea476a9130 100644 --- a/drivers/platform/x86/intel_scu_ipc.c +++ b/drivers/platform/x86/intel_scu_ipc.c @@ -60,6 +60,7 @@ #define IPC_WWBUF_SIZE 20 /* IPC Write buffer Size */ #define IPC_RWBUF_SIZE 20 /* IPC Read buffer Size */ +#define IPC_IOC 0x100 /* IPC command register IOC bit */ enum { SCU_IPC_LINCROFT, @@ -74,6 +75,7 @@ struct intel_scu_ipc_pdata_t { u32 i2c_base; u32 ipc_len; u32 i2c_len; + u8 irq_mode; }; static struct intel_scu_ipc_pdata_t intel_scu_ipc_pdata[] = { @@ -82,24 +84,28 @@ static struct intel_scu_ipc_pdata_t intel_scu_ipc_pdata[] = { .i2c_base = 0xff12b000, .ipc_len = 0x100, .i2c_len = 0x10, + .irq_mode = 0, }, [SCU_IPC_PENWELL] = { .ipc_base = 0xff11c000, .i2c_base = 0xff12b000, .ipc_len = 0x100, .i2c_len = 0x10, + .irq_mode = 1, }, [SCU_IPC_CLOVERVIEW] = { .ipc_base = 0xff11c000, .i2c_base = 0xff12b000, .ipc_len = 0x100, .i2c_len = 0x10, + .irq_mode = 1, }, [SCU_IPC_TANGIER] = { .ipc_base = 0xff009000, .i2c_base = 0xff00d000, .ipc_len = 0x100, .i2c_len = 0x10, + .irq_mode = 0, }, }; @@ -110,6 +116,8 @@ struct intel_scu_ipc_dev { struct pci_dev *pdev; void __iomem *ipc_base; void __iomem *i2c_base; + struct completion cmd_complete; + u8 irq_mode; }; static struct intel_scu_ipc_dev ipcdev; /* Only one for now */ @@ -136,6 +144,10 @@ static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */ */ static inline void ipc_command(u32 cmd) /* Send ipc command */ { + if (ipcdev.irq_mode) { + reinit_completion(&ipcdev.cmd_complete); + writel(cmd | IPC_IOC, ipcdev.ipc_base); + } writel(cmd, ipcdev.ipc_base); } @@ -194,6 +206,30 @@ static inline int busy_loop(void) /* Wait till scu status is busy */ return 0; } +/* Wait till ipc ioc interrupt is received or timeout in 3 HZ */ +static inline int ipc_wait_for_interrupt(void) +{ + int status; + + if (!wait_for_completion_timeout(&ipcdev.cmd_complete, 3 * HZ)) { + struct device *dev = &ipcdev.pdev->dev; + dev_err(dev, "IPC timed out\n"); + return -ETIMEDOUT; + } + + status = ipc_read_status(); + + if ((status >> 1) & 1) + return -EIO; + + return 0; +} + +int intel_scu_ipc_check_status(void) +{ + return ipcdev.irq_mode ? ipc_wait_for_interrupt() : busy_loop(); +} + /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */ static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id) { @@ -234,7 +270,7 @@ static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id) ipc_command(4 << 16 | id << 12 | 0 << 8 | op); } - err = busy_loop(); + err = intel_scu_ipc_check_status(); if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */ /* Workaround: values are read as 0 without memcpy_fromio */ memcpy_fromio(cbuf, ipcdev.ipc_base + 0x90, 16); @@ -429,7 +465,7 @@ int intel_scu_ipc_simple_command(int cmd, int sub) return -ENODEV; } ipc_command(sub << 12 | cmd); - err = busy_loop(); + err = intel_scu_ipc_check_status(); mutex_unlock(&ipclock); return err; } @@ -463,7 +499,7 @@ int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen, ipc_data_writel(*in++, 4 * i); ipc_command((inlen << 16) | (sub << 12) | cmd); - err = busy_loop(); + err = intel_scu_ipc_check_status(); if (!err) { for (i = 0; i < outlen; i++) @@ -531,6 +567,9 @@ EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl); */ static irqreturn_t ioc(int irq, void *dev_id) { + if (ipcdev.irq_mode) + complete(&ipcdev.cmd_complete); + return IRQ_HANDLED; } @@ -555,6 +594,7 @@ static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id) pdata = &intel_scu_ipc_pdata[pid]; ipcdev.pdev = pci_dev_get(dev); + ipcdev.irq_mode = pdata->irq_mode; err = pci_enable_device(dev); if (err) @@ -568,6 +608,8 @@ static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id) if (!pci_resource) return -ENOMEM; + init_completion(&ipcdev.cmd_complete); + if (request_irq(dev->irq, ioc, 0, "intel_scu_ipc", &ipcdev)) return -EBUSY; -- 2.20.1