[PATCH] PCI Hotplug: cpqphp 66/100/133MHz PCI-X support
drivers/hotplug/cpqphp.h | 194 +++++++++++++++++++++++++++++++++++++++++-
drivers/hotplug/cpqphp_core.c | 59 +++++++++++-
drivers/hotplug/cpqphp_ctrl.c | 147 +++++++++++++++++--------------
3 files changed, 323 insertions(+), 77 deletions(-)
diff -Nru a/drivers/hotplug/cpqphp.h b/drivers/hotplug/cpqphp.h
--- a/drivers/hotplug/cpqphp.h Fri May 2 11:39:09 2003
+++ b/drivers/hotplug/cpqphp.h Fri May 2 11:39:09 2003
@@ -30,7 +30,7 @@
#include "pci_hotplug.h"
#include <asm/io.h> /* for read? and write? functions */
-
+#include <linux/delay.h> /* for delays */
#if !defined(CONFIG_HOTPLUG_PCI_COMPAQ_MODULE)
#define MY_NAME "cpqphp.o"
@@ -145,6 +145,10 @@
u8 reserved11; /* 0x2b */
u8 slot_SERR; /* 0x2c */
u8 slot_power; /* 0x2d */
+ u8 reserved12; /* 0x2e */
+ u8 reserved13; /* 0x2f */
+ u8 next_curr_freq; /* 0x30 */
+ u8 reset_freq_mode; /* 0x31 */
} __attribute__ ((packed));
/* offsets to the controller registers based on the above structure layout */
@@ -172,6 +176,8 @@
CTRL_RESERVED11 = offsetof(struct ctrl_reg, reserved11),
SLOT_SERR = offsetof(struct ctrl_reg, slot_SERR),
SLOT_POWER = offsetof(struct ctrl_reg, slot_power),
+ NEXT_CURR_FREQ = offsetof(struct ctrl_reg, next_curr_freq),
+ RESET_FREQ_MODE = offsetof(struct ctrl_reg, reset_freq_mode),
};
struct hrt {
@@ -345,6 +351,7 @@
#define PCI_SUB_HPC_ID2 0xA2F8
#define PCI_SUB_HPC_ID3 0xA2F9
#define PCI_SUB_HPC_ID_INTC 0xA2FA
+#define PCI_SUB_HPC_ID4 0xA2FD
#define INT_BUTTON_IGNORE 0
#define INT_PRESENCE_ON 1
@@ -460,6 +467,7 @@
extern void cpqhp_destroy_resource_list (struct resource_lists * resources);
extern int cpqhp_configure_device (struct controller* ctrl, struct pci_func* func);
extern int cpqhp_unconfigure_device (struct pci_func* func);
+extern struct slot *cpqhp_find_slot (struct controller *ctrl, u8 device);
/* Global variables */
@@ -473,8 +481,6 @@
-/* inline functions */
-
/* Inline functions to check the sanity of a pointer that is passed to us */
static inline int slot_paranoia_check (struct slot *slot, const char *function)
@@ -588,6 +594,7 @@
u32 led_control;
led_control = readl(ctrl->hpc_reg + LED_CONTROL);
+ led_control &= ~(0x0101L << slot);
led_control |= (0x0001L << slot);
writel(led_control, ctrl->hpc_reg + LED_CONTROL);
}
@@ -629,14 +636,62 @@
}
+/*
+ * get_controller_speed - find the current frequency/mode of controller.
+ *
+ * @ctrl: controller to get frequency/mode for.
+ *
+ * Returns controller speed.
+ *
+ */
static inline u8 get_controller_speed (struct controller *ctrl)
{
+ u8 curr_freq;
u16 misc;
+ if (ctrl->pcix_support) {
+ curr_freq = readb(ctrl->hpc_reg + NEXT_CURR_FREQ);
+ if ((curr_freq & 0xB0) == 0xB0)
+ return PCI_SPEED_133MHz_PCIX;
+ if ((curr_freq & 0xA0) == 0xA0)
+ return PCI_SPEED_100MHz_PCIX;
+ if ((curr_freq & 0x90) == 0x90)
+ return PCI_SPEED_66MHz_PCIX;
+ if (curr_freq & 0x10)
+ return PCI_SPEED_66MHz;
+
+ return PCI_SPEED_33MHz;
+ }
+
misc = readw(ctrl->hpc_reg + MISC);
return (misc & 0x0800) ? PCI_SPEED_66MHz : PCI_SPEED_33MHz;
}
+/*
+ * get_adapter_speed - find the max supported frequency/mode of adapter.
+ *
+ * @ctrl: hotplug controller.
+ * @hp_slot: hotplug slot where adapter is installed.
+ *
+ * Returns adapter speed.
+ *
+ */
+static inline u8 get_adapter_speed (struct controller *ctrl, u8 hp_slot)
+{
+ u32 temp_dword = readl(ctrl->hpc_reg + NON_INT_INPUT);
+ dbg("slot: %d, PCIXCAP: %8x\n", hp_slot, temp_dword);
+ if (ctrl->pcix_support) {
+ if (temp_dword & (0x10000 << hp_slot))
+ return PCI_SPEED_133MHz_PCIX;
+ if (temp_dword & (0x100 << hp_slot))
+ return PCI_SPEED_66MHz_PCIX;
+ }
+
+ if (temp_dword & (0x01 << hp_slot))
+ return PCI_SPEED_66MHz;
+
+ return PCI_SPEED_33MHz;
+}
static inline void enable_slot_power (struct controller *ctrl, u8 slot)
{
@@ -744,5 +799,136 @@
return retval;
}
-#endif
+/**
+ * set_controller_speed - set the frequency and/or mode of a specific
+ * controller segment.
+ *
+ * @ctrl: controller to change frequency/mode for.
+ * @adapter_speed: the speed of the adapter we want to match.
+ * @hp_slot: the slot number where the adapter is installed.
+ *
+ * Returns 0 if we successfully change frequency and/or mode to match the
+ * adapter speed.
+ *
+ */
+static inline u8 set_controller_speed(struct controller *ctrl, u8 adapter_speed, u8 hp_slot)
+{
+ struct slot *slot;
+ u8 reg;
+ u8 slot_power = readb(ctrl->hpc_reg + SLOT_POWER);
+ u16 reg16;
+ u32 leds = readl(ctrl->hpc_reg + LED_CONTROL);
+
+ if (ctrl->speed == adapter_speed)
+ return 0;
+
+ /* We don't allow freq/mode changes if we find another adapter running
+ * in another slot on this controller */
+ for(slot = ctrl->slot; slot; slot = slot->next) {
+ if (slot->device == (hp_slot + ctrl->slot_device_offset))
+ continue;
+ if (!slot->hotplug_slot && !slot->hotplug_slot->info)
+ continue;
+ if (slot->hotplug_slot->info->adapter_status == 0)
+ continue;
+ /* If another adapter is running on the same segment but at a
+ * lower speed/mode, we allow the new adapter to function at
+ * this rate if supported */
+ if (ctrl->speed < adapter_speed)
+ return 0;
+
+ return 1;
+ }
+
+ /* If the controller doesn't support freq/mode changes and the
+ * controller is running at a higher mode, we bail */
+ if ((ctrl->speed > adapter_speed) && (!ctrl->pcix_speed_capability))
+ return 1;
+
+ /* But we allow the adapter to run at a lower rate if possible */
+ if ((ctrl->speed < adapter_speed) && (!ctrl->pcix_speed_capability))
+ return 0;
+
+ /* We try to set the max speed supported by both the adapter and
+ * controller */
+ if (ctrl->speed_capability < adapter_speed) {
+ if (ctrl->speed == ctrl->speed_capability)
+ return 0;
+ adapter_speed = ctrl->speed_capability;
+ }
+
+ writel(0x0L, ctrl->hpc_reg + LED_CONTROL);
+ writeb(0x00, ctrl->hpc_reg + SLOT_ENABLE);
+
+ set_SOGO(ctrl);
+ wait_for_ctrl_irq(ctrl);
+
+ if (adapter_speed != PCI_SPEED_133MHz_PCIX)
+ reg = 0xF5;
+ else
+ reg = 0xF4;
+ pci_write_config_byte(ctrl->pci_dev, 0x41, reg);
+
+ reg16 = readw(ctrl->hpc_reg + NEXT_CURR_FREQ);
+ reg16 &= ~0x000F;
+ switch(adapter_speed) {
+ case(PCI_SPEED_133MHz_PCIX):
+ reg = 0x75;
+ reg16 |= 0xB;
+ break;
+ case(PCI_SPEED_100MHz_PCIX):
+ reg = 0x74;
+ reg16 |= 0xA;
+ break;
+ case(PCI_SPEED_66MHz_PCIX):
+ reg = 0x73;
+ reg16 |= 0x9;
+ break;
+ case(PCI_SPEED_66MHz):
+ reg = 0x73;
+ reg16 |= 0x1;
+ break;
+ default: /* 33MHz PCI 2.2 */
+ reg = 0x71;
+ break;
+
+ }
+ reg16 |= 0xB << 12;
+ writew(reg16, ctrl->hpc_reg + NEXT_CURR_FREQ);
+
+ mdelay(5);
+
+ /* Reenable interrupts */
+ writel(0, ctrl->hpc_reg + INT_MASK);
+
+ pci_write_config_byte(ctrl->pci_dev, 0x41, reg);
+
+ /* Restart state machine */
+ reg = ~0xF;
+ pci_read_config_byte(ctrl->pci_dev, 0x43, ®);
+ pci_write_config_byte(ctrl->pci_dev, 0x43, reg);
+
+ /* Only if mode change...*/
+ if (((ctrl->speed == PCI_SPEED_66MHz) && (adapter_speed == PCI_SPEED_66MHz_PCIX)) ||
+ ((ctrl->speed == PCI_SPEED_66MHz_PCIX) && (adapter_speed == PCI_SPEED_66MHz)))
+ set_SOGO(ctrl);
+
+ wait_for_ctrl_irq(ctrl);
+ mdelay(1100);
+
+ /* Restore LED/Slot state */
+ writel(leds, ctrl->hpc_reg + LED_CONTROL);
+ writeb(slot_power, ctrl->hpc_reg + SLOT_ENABLE);
+
+ set_SOGO(ctrl);
+ wait_for_ctrl_irq(ctrl);
+
+ ctrl->speed = adapter_speed;
+ slot = cpqhp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
+ info("Successfully changed frequency/mode for adapter in slot %d\n",
+ slot->number);
+ return 0;
+}
+
+#endif
diff -Nru a/drivers/hotplug/cpqphp_core.c b/drivers/hotplug/cpqphp_core.c
--- a/drivers/hotplug/cpqphp_core.c Fri May 2 11:39:08 2003
+++ b/drivers/hotplug/cpqphp_core.c Fri May 2 11:39:09 2003
@@ -24,6 +24,9 @@
*
* Send feedback to <greg@kroah.com>
*
+ * Jan 12, 2003 - Added 66/100/133MHz PCI-X support,
+ * Torben Mathiasen <torben.mathiasen@hp.com>
+ *
*/
#include <linux/config.h>
@@ -53,7 +56,7 @@
static u8 power_mode;
static int debug;
-#define DRIVER_VERSION "0.9.6"
+#define DRIVER_VERSION "0.9.7"
#define DRIVER_AUTHOR "Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>"
#define DRIVER_DESC "Compaq Hot Plug PCI Controller Driver"
@@ -829,6 +832,7 @@
u8 hp_slot = 0;
u8 device;
u8 rev;
+ u8 bus_cap;
u16 temp_word;
u16 vendor_id;
u16 subsystem_vid;
@@ -890,6 +894,39 @@
switch (subsystem_vid) {
case PCI_VENDOR_ID_COMPAQ:
+ if (rev >= 0x13) { /* CIOBX */
+ ctrl->push_flag = 1;
+ ctrl->slot_switch_type = 1; // Switch is present
+ ctrl->push_button = 1; // Pushbutton is present
+ ctrl->pci_config_space = 1; // Index/data access to working registers 0 = not supported, 1 = supported
+ ctrl->defeature_PHP = 1; // PHP is supported
+ ctrl->pcix_support = 1; // PCI-X supported
+ ctrl->pcix_speed_capability = 1;
+ pci_read_config_byte(pdev, 0x41, &bus_cap);
+ if (bus_cap & 0x80) {
+ dbg("bus max supports 133MHz PCI-X\n");
+ ctrl->speed_capability = PCI_SPEED_133MHz_PCIX;
+ break;
+ }
+ if (bus_cap & 0x40) {
+ dbg("bus max supports 100MHz PCI-X\n");
+ ctrl->speed_capability = PCI_SPEED_100MHz_PCIX;
+ break;
+ }
+ if (bus_cap & 20) {
+ dbg("bus max supports 66MHz PCI-X\n");
+ ctrl->speed_capability = PCI_SPEED_66MHz_PCIX;
+ break;
+ }
+ if (bus_cap & 10) {
+ dbg("bus max supports 66MHz PCI\n");
+ ctrl->speed_capability = PCI_SPEED_66MHz;
+ break;
+ }
+
+ break;
+ }
+
switch (subsystem_deviceid) {
case PCI_SUB_HPC_ID:
/* Original 6500/7000 implementation */
@@ -933,8 +970,18 @@
ctrl->pcix_support = 0; // PCI-X not supported
ctrl->pcix_speed_capability = 0; // N/A since PCI-X not supported
break;
+ case PCI_SUB_HPC_ID4:
+ /* First PCI-X implementation, 100MHz */
+ ctrl->push_flag = 1;
+ ctrl->slot_switch_type = 1; // Switch is present
+ ctrl->speed_capability = PCI_SPEED_100MHz_PCIX;
+ ctrl->push_button = 1; // Pushbutton is present
+ ctrl->pci_config_space = 1; // Index/data access to working registers 0 = not supported, 1 = supported
+ ctrl->defeature_PHP = 1; // PHP is supported
+ ctrl->pcix_support = 1; // PCI-X supported
+ ctrl->pcix_speed_capability = 0;
+ break;
default:
- // TODO: Add SSIDs for CPQ systems that support PCI-X
err(msg_HPC_not_supported);
rc = -ENODEV;
goto err_free_ctrl;
@@ -1023,7 +1070,7 @@
info("Initializing the PCI hot plug controller residing on PCI bus %d\n", pdev->bus->number);
dbg ("Hotplug controller capabilities:\n");
- dbg (" speed_capability %s\n", ctrl->speed_capability == PCI_SPEED_33MHz ? "33MHz" : "66Mhz");
+ dbg (" speed_capability %d\n", ctrl->speed_capability);
dbg (" slot_switch_type %s\n", ctrl->slot_switch_type == 0 ? "no switch" : "switch present");
dbg (" defeature_PHP %s\n", ctrl->defeature_PHP == 0 ? "PHP not supported" : "PHP supported");
dbg (" alternate_base_address %s\n", ctrl->alternate_base_address == 0 ? "not supported" : "supported");
@@ -1066,11 +1113,9 @@
goto err_free_mem_region;
}
- // Check for 66Mhz operation
- // TODO: Add PCI-X support
+ // Check for 66Mhz and/or PCI-X operation
ctrl->speed = get_controller_speed(ctrl);
-
-
+
//**************************************************
//
// Save configuration headers for this and
diff -Nru a/drivers/hotplug/cpqphp_ctrl.c b/drivers/hotplug/cpqphp_ctrl.c
--- a/drivers/hotplug/cpqphp_ctrl.c Fri May 2 11:39:09 2003
+++ b/drivers/hotplug/cpqphp_ctrl.c Fri May 2 11:39:09 2003
@@ -135,9 +135,9 @@
/*
- * find_slot
+ * cpqhp_find_slot
*/
-static inline struct slot *find_slot (struct controller * ctrl, u8 device)
+struct slot *cpqhp_find_slot (struct controller * ctrl, u8 device)
{
struct slot *slot;
@@ -186,7 +186,7 @@
rc++;
- p_slot = find_slot(ctrl, hp_slot + (readb(ctrl->hpc_reg + SLOT_MASK) >> 4));
+ p_slot = cpqhp_find_slot(ctrl, hp_slot + (readb(ctrl->hpc_reg + SLOT_MASK) >> 4));
// If the switch closed, must be a button
// If not in button mode, nevermind
@@ -916,6 +916,7 @@
void cpqhp_ctrl_intr(int IRQ, struct controller * ctrl, struct pt_regs *regs)
{
u8 schedule_flag = 0;
+ u8 reset;
u16 misc;
u32 Diff;
u32 temp_dword;
@@ -966,6 +967,15 @@
schedule_flag += handle_presence_change((u16)((Diff & 0xFFFF0000L) >> 16), ctrl);
schedule_flag += handle_power_fault((u8)((Diff & 0xFF00L) >> 8), ctrl);
}
+
+ reset = readb(ctrl->hpc_reg + RESET_FREQ_MODE);
+ if (reset & 0x40) {
+ /* Bus Reset has completed */
+ reset &= 0xCF;
+ writeb(reset, ctrl->hpc_reg + RESET_FREQ_MODE);
+ reset = readb(ctrl->hpc_reg + RESET_FREQ_MODE);
+ wake_up_interruptible(&ctrl->queue);
+ }
if (schedule_flag) {
up(&event_semaphore);
@@ -1169,6 +1179,7 @@
{
u8 hp_slot;
u8 temp_byte;
+ u8 adapter_speed;
u32 index;
u32 rc = 0;
u32 src = 8;
@@ -1186,46 +1197,47 @@
//*********************************
rc = CARD_FUNCTIONING;
} else {
- if (ctrl->speed == PCI_SPEED_66MHz) {
- // Wait for exclusive access to hardware
- down(&ctrl->crit_sect);
-
- // turn on board without attaching to the bus
- enable_slot_power (ctrl, hp_slot);
+ // Wait for exclusive access to hardware
+ down(&ctrl->crit_sect);
- set_SOGO(ctrl);
+ // turn on board without attaching to the bus
+ enable_slot_power (ctrl, hp_slot);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ set_SOGO(ctrl);
- // Change bits in slot power register to force another shift out
- // NOTE: this is to work around the timer bug
- temp_byte = readb(ctrl->hpc_reg + SLOT_POWER);
- writeb(0x00, ctrl->hpc_reg + SLOT_POWER);
- writeb(temp_byte, ctrl->hpc_reg + SLOT_POWER);
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
- set_SOGO(ctrl);
+ // Change bits in slot power register to force another shift out
+ // NOTE: this is to work around the timer bug
+ temp_byte = readb(ctrl->hpc_reg + SLOT_POWER);
+ writeb(0x00, ctrl->hpc_reg + SLOT_POWER);
+ writeb(temp_byte, ctrl->hpc_reg + SLOT_POWER);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ set_SOGO(ctrl);
- if (!(readl(ctrl->hpc_reg + NON_INT_INPUT) & (0x01 << hp_slot))) {
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
+
+ // 66MHz and/or PCI-X support check
+ adapter_speed = get_adapter_speed(ctrl, hp_slot);
+ if (ctrl->speed != adapter_speed)
+ if (set_controller_speed(ctrl, adapter_speed, hp_slot))
rc = WRONG_BUS_FREQUENCY;
- }
- // turn off board without attaching to the bus
- disable_slot_power (ctrl, hp_slot);
- set_SOGO(ctrl);
+ // turn off board without attaching to the bus
+ disable_slot_power (ctrl, hp_slot);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ set_SOGO(ctrl);
- // Done with exclusive hardware access
- up(&ctrl->crit_sect);
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
- if (rc)
- return(rc);
- }
+ // Done with exclusive hardware access
+ up(&ctrl->crit_sect);
+
+ if (rc)
+ return(rc);
// Wait for exclusive access to hardware
down(&ctrl->crit_sect);
@@ -1373,6 +1385,7 @@
{
u8 hp_slot;
u8 temp_byte;
+ u8 adapter_speed;
int index;
u32 temp_register = 0xFFFFFFFF;
u32 rc = 0;
@@ -1383,48 +1396,50 @@
hp_slot = func->device - ctrl->slot_device_offset;
dbg(__FUNCTION__": func->device, slot_offset, hp_slot = %d, %d ,%d\n",
func->device, ctrl->slot_device_offset, hp_slot);
+
+ // Wait for exclusive access to hardware
+ down(&ctrl->crit_sect);
- if (ctrl->speed == PCI_SPEED_66MHz) {
- // Wait for exclusive access to hardware
- down(&ctrl->crit_sect);
-
- // turn on board without attaching to the bus
- enable_slot_power (ctrl, hp_slot);
-
- set_SOGO(ctrl);
+ // turn on board without attaching to the bus
+ enable_slot_power (ctrl, hp_slot);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ set_SOGO(ctrl);
- // Change bits in slot power register to force another shift out
- // NOTE: this is to work around the timer bug
- temp_byte = readb(ctrl->hpc_reg + SLOT_POWER);
- writeb(0x00, ctrl->hpc_reg + SLOT_POWER);
- writeb(temp_byte, ctrl->hpc_reg + SLOT_POWER);
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
- set_SOGO(ctrl);
+ // Change bits in slot power register to force another shift out
+ // NOTE: this is to work around the timer bug
+ temp_byte = readb(ctrl->hpc_reg + SLOT_POWER);
+ writeb(0x00, ctrl->hpc_reg + SLOT_POWER);
+ writeb(temp_byte, ctrl->hpc_reg + SLOT_POWER);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ set_SOGO(ctrl);
- if (!(readl(ctrl->hpc_reg + NON_INT_INPUT) & (0x01 << hp_slot))) {
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
+
+ // 66MHz and/or PCI-X support check
+ adapter_speed = get_adapter_speed(ctrl, hp_slot);
+ if (ctrl->speed != adapter_speed)
+ if (set_controller_speed(ctrl, adapter_speed, hp_slot))
rc = WRONG_BUS_FREQUENCY;
- }
- // turn off board without attaching to the bus
- disable_slot_power (ctrl, hp_slot);
+
+ // turn off board without attaching to the bus
+ disable_slot_power (ctrl, hp_slot);
- set_SOGO(ctrl);
+ set_SOGO(ctrl);
- // Wait for SOBS to be unset
- wait_for_ctrl_irq (ctrl);
+ // Wait for SOBS to be unset
+ wait_for_ctrl_irq (ctrl);
- // Done with exclusive hardware access
- up(&ctrl->crit_sect);
+ // Done with exclusive hardware access
+ up(&ctrl->crit_sect);
- if (rc)
- return(rc);
- }
- p_slot = find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
+ if (rc)
+ return(rc);
+
+ p_slot = cpqhp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
// turn on board and blink green LED
@@ -1800,7 +1815,7 @@
func = cpqhp_slot_find(ctrl->bus, (hp_slot + ctrl->slot_device_offset), 0);
- p_slot = find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
+ p_slot = cpqhp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
dbg("hp_slot %d, func %p, p_slot %p\n",
hp_slot, func, p_slot);
@@ -1990,7 +2005,7 @@
device = func->device;
hp_slot = device - ctrl->slot_device_offset;
- p_slot = find_slot(ctrl, device);
+ p_slot = cpqhp_find_slot(ctrl, device);
if (p_slot) {
physical_slot = p_slot->number;
}
@@ -2087,7 +2102,7 @@
device = func->device;
func = cpqhp_slot_find(ctrl->bus, device, index++);
- p_slot = find_slot(ctrl, device);
+ p_slot = cpqhp_find_slot(ctrl, device);
if (p_slot) {
physical_slot = p_slot->number;
}
-
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