diff options
| -rw-r--r-- | drivers/mailbox/pcc.c | 316 |
1 files changed, 245 insertions, 71 deletions
diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c index 043828d541f7..08c87fadca8c 100644 --- a/drivers/mailbox/pcc.c +++ b/drivers/mailbox/pcc.c @@ -59,6 +59,7 @@ #include <linux/delay.h> #include <linux/io.h> #include <linux/init.h> +#include <linux/interrupt.h> #include <linux/list.h> #include <linux/platform_device.h> #include <linux/mailbox_controller.h> @@ -68,11 +69,16 @@ #include "mailbox.h" #define MAX_PCC_SUBSPACES 256 +#define MBOX_IRQ_NAME "pcc-mbox" static struct mbox_chan *pcc_mbox_channels; /* Array of cached virtual address for doorbell registers */ static void __iomem **pcc_doorbell_vaddr; +/* Array of cached virtual address for doorbell ack registers */ +static void __iomem **pcc_doorbell_ack_vaddr; +/* Array of doorbell interrupts */ +static int *pcc_doorbell_irq; static struct mbox_controller pcc_mbox_ctrl = {}; /** @@ -91,6 +97,132 @@ static struct mbox_chan *get_pcc_channel(int id) return &pcc_mbox_channels[id]; } +/* + * PCC can be used with perf critical drivers such as CPPC + * So it makes sense to locally cache the virtual address and + * use it to read/write to PCC registers such as doorbell register + * + * The below read_register and write_registers are used to read and + * write from perf critical registers such as PCC doorbell register + */ +static int read_register(void __iomem *vaddr, u64 *val, unsigned int bit_width) +{ + int ret_val = 0; + + switch (bit_width) { + case 8: + *val = readb(vaddr); + break; + case 16: + *val = readw(vaddr); + break; + case 32: + *val = readl(vaddr); + break; + case 64: + *val = readq(vaddr); + break; + default: + pr_debug("Error: Cannot read register of %u bit width", + bit_width); + ret_val = -EFAULT; + break; + } + return ret_val; +} + +static int write_register(void __iomem *vaddr, u64 val, unsigned int bit_width) +{ + int ret_val = 0; + + switch (bit_width) { + case 8: + writeb(val, vaddr); + break; + case 16: + writew(val, vaddr); + break; + case 32: + writel(val, vaddr); + break; + case 64: + writeq(val, vaddr); + break; + default: + pr_debug("Error: Cannot write register of %u bit width", + bit_width); + ret_val = -EFAULT; + break; + } + return ret_val; +} + +/** + * pcc_map_interrupt - Map a PCC subspace GSI to a linux IRQ number + * @interrupt: GSI number. + * @flags: interrupt flags + * + * Returns: a valid linux IRQ number on success + * 0 or -EINVAL on failure + */ +static int pcc_map_interrupt(u32 interrupt, u32 flags) +{ + int trigger, polarity; + + if (!interrupt) + return 0; + + trigger = (flags & ACPI_PCCT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE + : ACPI_LEVEL_SENSITIVE; + + polarity = (flags & ACPI_PCCT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW + : ACPI_ACTIVE_HIGH; + + return acpi_register_gsi(NULL, interrupt, trigger, polarity); +} + +/** + * pcc_mbox_irq - PCC mailbox interrupt handler + */ +static irqreturn_t pcc_mbox_irq(int irq, void *p) +{ + struct acpi_generic_address *doorbell_ack; + struct acpi_pcct_hw_reduced *pcct_ss; + struct mbox_chan *chan = p; + u64 doorbell_ack_preserve; + u64 doorbell_ack_write; + u64 doorbell_ack_val; + int ret; + + pcct_ss = chan->con_priv; + + mbox_chan_received_data(chan, NULL); + + if (pcct_ss->header.type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) { + struct acpi_pcct_hw_reduced_type2 *pcct2_ss = chan->con_priv; + u32 id = chan - pcc_mbox_channels; + + doorbell_ack = &pcct2_ss->doorbell_ack_register; + doorbell_ack_preserve = pcct2_ss->ack_preserve_mask; + doorbell_ack_write = pcct2_ss->ack_write_mask; + + ret = read_register(pcc_doorbell_ack_vaddr[id], + &doorbell_ack_val, + doorbell_ack->bit_width); + if (ret) + return IRQ_NONE; + + ret = write_register(pcc_doorbell_ack_vaddr[id], + (doorbell_ack_val & doorbell_ack_preserve) + | doorbell_ack_write, + doorbell_ack->bit_width); + if (ret) + return IRQ_NONE; + } + + return IRQ_HANDLED; +} + /** * pcc_mbox_request_channel - PCC clients call this function to * request a pointer to their PCC subspace, from which they @@ -135,6 +267,18 @@ struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl, if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone) chan->txdone_method |= TXDONE_BY_ACK; + if (pcc_doorbell_irq[subspace_id] > 0) { + int rc; + + rc = devm_request_irq(dev, pcc_doorbell_irq[subspace_id], + pcc_mbox_irq, 0, MBOX_IRQ_NAME, chan); + if (unlikely(rc)) { + dev_err(dev, "failed to register PCC interrupt %d\n", + pcc_doorbell_irq[subspace_id]); + chan = ERR_PTR(rc); + } + } + spin_unlock_irqrestore(&chan->lock, flags); return chan; @@ -149,80 +293,30 @@ EXPORT_SYMBOL_GPL(pcc_mbox_request_channel); */ void pcc_mbox_free_channel(struct mbox_chan *chan) { + u32 id = chan - pcc_mbox_channels; unsigned long flags; if (!chan || !chan->cl) return; + if (id >= pcc_mbox_ctrl.num_chans) { + pr_debug("pcc_mbox_free_channel: Invalid mbox_chan passed\n"); + return; + } + spin_lock_irqsave(&chan->lock, flags); chan->cl = NULL; chan->active_req = NULL; if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK)) chan->txdone_method = TXDONE_BY_POLL; + if (pcc_doorbell_irq[id] > 0) + devm_free_irq(chan->mbox->dev, pcc_doorbell_irq[id], chan); + spin_unlock_irqrestore(&chan->lock, flags); } EXPORT_SYMBOL_GPL(pcc_mbox_free_channel); -/* - * PCC can be used with perf critical drivers such as CPPC - * So it makes sense to locally cache the virtual address and - * use it to read/write to PCC registers such as doorbell register - * - * The below read_register and write_registers are used to read and - * write from perf critical registers such as PCC doorbell register - */ -static int read_register(void __iomem *vaddr, u64 *val, unsigned int bit_width) -{ - int ret_val = 0; - - switch (bit_width) { - case 8: - *val = readb(vaddr); - break; - case 16: - *val = readw(vaddr); - break; - case 32: - *val = readl(vaddr); - break; - case 64: - *val = readq(vaddr); - break; - default: - pr_debug("Error: Cannot read register of %u bit width", - bit_width); - ret_val = -EFAULT; - break; - } - return ret_val; -} - -static int write_register(void __iomem *vaddr, u64 val, unsigned int bit_width) -{ - int ret_val = 0; - - switch (bit_width) { - case 8: - writeb(val, vaddr); - break; - case 16: - writew(val, vaddr); - break; - case 32: - writel(val, vaddr); - break; - case 64: - writeq(val, vaddr); - break; - default: - pr_debug("Error: Cannot write register of %u bit width", - bit_width); - ret_val = -EFAULT; - break; - } - return ret_val; -} /** * pcc_send_data - Called from Mailbox Controller code. Used @@ -296,8 +390,10 @@ static int parse_pcc_subspace(struct acpi_subtable_header *header, if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) { pcct_ss = (struct acpi_pcct_hw_reduced *) header; - if (pcct_ss->header.type != - ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE) { + if ((pcct_ss->header.type != + ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE) + && (pcct_ss->header.type != + ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2)) { pr_err("Incorrect PCC Subspace type detected\n"); return -EINVAL; } @@ -307,6 +403,43 @@ static int parse_pcc_subspace(struct acpi_subtable_header *header, } /** + * pcc_parse_subspace_irq - Parse the PCC IRQ and PCC ACK register + * There should be one entry per PCC client. + * @id: PCC subspace index. + * @pcct_ss: Pointer to the ACPI subtable header under the PCCT. + * + * Return: 0 for Success, else errno. + * + * This gets called for each entry in the PCC table. + */ +static int pcc_parse_subspace_irq(int id, + struct acpi_pcct_hw_reduced *pcct_ss) +{ + pcc_doorbell_irq[id] = pcc_map_interrupt(pcct_ss->doorbell_interrupt, + (u32)pcct_ss->flags); + if (pcc_doorbell_irq[id] <= 0) { + pr_err("PCC GSI %d not registered\n", + pcct_ss->doorbell_interrupt); + return -EINVAL; + } + + if (pcct_ss->header.type + == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) { + struct acpi_pcct_hw_reduced_type2 *pcct2_ss = (void *)pcct_ss; + + pcc_doorbell_ack_vaddr[id] = acpi_os_ioremap( + pcct2_ss->doorbell_ack_register.address, + pcct2_ss->doorbell_ack_register.bit_width / 8); + if (!pcc_doorbell_ack_vaddr[id]) { + pr_err("Failed to ioremap PCC ACK register\n"); + return -ENOMEM; + } + } + + return 0; +} + +/** * acpi_pcc_probe - Parse the ACPI tree for the PCCT. * * Return: 0 for Success, else errno. @@ -316,7 +449,9 @@ static int __init acpi_pcc_probe(void) acpi_size pcct_tbl_header_size; struct acpi_table_header *pcct_tbl; struct acpi_subtable_header *pcct_entry; - int count, i; + struct acpi_table_pcct *acpi_pcct_tbl; + int count, i, rc; + int sum = 0; acpi_status status = AE_OK; /* Search for PCCT */ @@ -333,37 +468,66 @@ static int __init acpi_pcc_probe(void) sizeof(struct acpi_table_pcct), ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE, parse_pcc_subspace, MAX_PCC_SUBSPACES); + sum += (count > 0) ? count : 0; + + count = acpi_table_parse_entries(ACPI_SIG_PCCT, + sizeof(struct acpi_table_pcct), + ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2, + parse_pcc_subspace, MAX_PCC_SUBSPACES); + sum += (count > 0) ? count : 0; - if (count <= 0) { + if (sum == 0 || sum >= MAX_PCC_SUBSPACES) { pr_err("Error parsing PCC subspaces from PCCT\n"); return -EINVAL; } pcc_mbox_channels = kzalloc(sizeof(struct mbox_chan) * - count, GFP_KERNEL); - + sum, GFP_KERNEL); if (!pcc_mbox_channels) { pr_err("Could not allocate space for PCC mbox channels\n"); return -ENOMEM; } - pcc_doorbell_vaddr = kcalloc(count, sizeof(void *), GFP_KERNEL); + pcc_doorbell_vaddr = kcalloc(sum, sizeof(void *), GFP_KERNEL); if (!pcc_doorbell_vaddr) { - kfree(pcc_mbox_channels); - return -ENOMEM; + rc = -ENOMEM; + goto err_free_mbox; + } + + pcc_doorbell_ack_vaddr = kcalloc(sum, sizeof(void *), GFP_KERNEL); + if (!pcc_doorbell_ack_vaddr) { + rc = -ENOMEM; + goto err_free_db_vaddr; + } + + pcc_doorbell_irq = kcalloc(sum, sizeof(int), GFP_KERNEL); + if (!pcc_doorbell_irq) { + rc = -ENOMEM; + goto err_free_db_ack_vaddr; } /* Point to the first PCC subspace entry */ pcct_entry = (struct acpi_subtable_header *) ( (unsigned long) pcct_tbl + sizeof(struct acpi_table_pcct)); - for (i = 0; i < count; i++) { + acpi_pcct_tbl = (struct acpi_table_pcct *) pcct_tbl; + if (acpi_pcct_tbl->flags & ACPI_PCCT_DOORBELL) + pcc_mbox_ctrl.txdone_irq = true; + + for (i = 0; i < sum; i++) { struct acpi_generic_address *db_reg; struct acpi_pcct_hw_reduced *pcct_ss; pcc_mbox_channels[i].con_priv = pcct_entry; + pcct_ss = (struct acpi_pcct_hw_reduced *) pcct_entry; + + if (pcc_mbox_ctrl.txdone_irq) { + rc = pcc_parse_subspace_irq(i, pcct_ss); + if (rc < 0) + goto err; + } + /* If doorbell is in system memory cache the virt address */ - pcct_ss = (struct acpi_pcct_hw_reduced *)pcct_entry; db_reg = &pcct_ss->doorbell_register; if (db_reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) pcc_doorbell_vaddr[i] = acpi_os_ioremap(db_reg->address, @@ -372,11 +536,21 @@ static int __init acpi_pcc_probe(void) ((unsigned long) pcct_entry + pcct_entry->length); } - pcc_mbox_ctrl.num_chans = count; + pcc_mbox_ctrl.num_chans = sum; pr_info("Detected %d PCC Subspaces\n", pcc_mbox_ctrl.num_chans); return 0; + +err: + kfree(pcc_doorbell_irq); +err_free_db_ack_vaddr: + kfree(pcc_doorbell_ack_vaddr); +err_free_db_vaddr: + kfree(pcc_doorbell_vaddr); +err_free_mbox: + kfree(pcc_mbox_channels); + return rc; } /** |