diff options
Diffstat (limited to 'arch/c6x/platforms/dscr.c')
-rw-r--r-- | arch/c6x/platforms/dscr.c | 595 |
1 files changed, 0 insertions, 595 deletions
diff --git a/arch/c6x/platforms/dscr.c b/arch/c6x/platforms/dscr.c deleted file mode 100644 index 4571615b589f..000000000000 --- a/arch/c6x/platforms/dscr.c +++ /dev/null @@ -1,595 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Device State Control Registers driver - * - * Copyright (C) 2011 Texas Instruments Incorporated - * Author: Mark Salter <msalter@redhat.com> - */ - -/* - * The Device State Control Registers (DSCR) provide SoC level control over - * a number of peripherals. Details vary considerably among the various SoC - * parts. In general, the DSCR block will provide one or more configuration - * registers often protected by a lock register. One or more key values must - * be written to a lock register in order to unlock the configuration register. - * The configuration register may be used to enable (and disable in some - * cases) SoC pin drivers, peripheral clock sources (internal or pin), etc. - * In some cases, a configuration register is write once or the individual - * bits are write once. That is, you may be able to enable a device, but - * will not be able to disable it. - * - * In addition to device configuration, the DSCR block may provide registers - * which are used to reset SoC peripherals, provide device ID information, - * provide MAC addresses, and other miscellaneous functions. - */ - -#include <linux/of.h> -#include <linux/of_address.h> -#include <linux/of_platform.h> -#include <linux/module.h> -#include <linux/io.h> -#include <linux/delay.h> -#include <asm/soc.h> -#include <asm/dscr.h> - -#define MAX_DEVSTATE_IDS 32 -#define MAX_DEVCTL_REGS 8 -#define MAX_DEVSTAT_REGS 8 -#define MAX_LOCKED_REGS 4 -#define MAX_SOC_EMACS 2 - -struct rmii_reset_reg { - u32 reg; - u32 mask; -}; - -/* - * Some registerd may be locked. In order to write to these - * registers, the key value must first be written to the lockreg. - */ -struct locked_reg { - u32 reg; /* offset from base */ - u32 lockreg; /* offset from base */ - u32 key; /* unlock key */ -}; - -/* - * This describes a contiguous area of like control bits used to enable/disable - * SoC devices. Each controllable device is given an ID which is used by the - * individual device drivers to control the device state. These IDs start at - * zero and are assigned sequentially to the control bitfield ranges described - * by this structure. - */ -struct devstate_ctl_reg { - u32 reg; /* register holding the control bits */ - u8 start_id; /* start id of this range */ - u8 num_ids; /* number of devices in this range */ - u8 enable_only; /* bits are write-once to enable only */ - u8 enable; /* value used to enable device */ - u8 disable; /* value used to disable device */ - u8 shift; /* starting (rightmost) bit in range */ - u8 nbits; /* number of bits per device */ -}; - - -/* - * This describes a region of status bits indicating the state of - * various devices. This is used internally to wait for status - * change completion when enabling/disabling a device. Status is - * optional and not all device controls will have a corresponding - * status. - */ -struct devstate_stat_reg { - u32 reg; /* register holding the status bits */ - u8 start_id; /* start id of this range */ - u8 num_ids; /* number of devices in this range */ - u8 enable; /* value indicating enabled state */ - u8 disable; /* value indicating disabled state */ - u8 shift; /* starting (rightmost) bit in range */ - u8 nbits; /* number of bits per device */ -}; - -struct devstate_info { - struct devstate_ctl_reg *ctl; - struct devstate_stat_reg *stat; -}; - -/* These are callbacks to SOC-specific code. */ -struct dscr_ops { - void (*init)(struct device_node *node); -}; - -struct dscr_regs { - spinlock_t lock; - void __iomem *base; - u32 kick_reg[2]; - u32 kick_key[2]; - struct locked_reg locked[MAX_LOCKED_REGS]; - struct devstate_info devstate_info[MAX_DEVSTATE_IDS]; - struct rmii_reset_reg rmii_resets[MAX_SOC_EMACS]; - struct devstate_ctl_reg devctl[MAX_DEVCTL_REGS]; - struct devstate_stat_reg devstat[MAX_DEVSTAT_REGS]; -}; - -static struct dscr_regs dscr; - -static struct locked_reg *find_locked_reg(u32 reg) -{ - int i; - - for (i = 0; i < MAX_LOCKED_REGS; i++) - if (dscr.locked[i].key && reg == dscr.locked[i].reg) - return &dscr.locked[i]; - return NULL; -} - -/* - * Write to a register with one lock - */ -static void dscr_write_locked1(u32 reg, u32 val, - u32 lock, u32 key) -{ - void __iomem *reg_addr = dscr.base + reg; - void __iomem *lock_addr = dscr.base + lock; - - /* - * For some registers, the lock is relocked after a short number - * of cycles. We have to put the lock write and register write in - * the same fetch packet to meet this timing. The .align ensures - * the two stw instructions are in the same fetch packet. - */ - asm volatile ("b .s2 0f\n" - "nop 5\n" - " .align 5\n" - "0:\n" - "stw .D1T2 %3,*%2\n" - "stw .D1T2 %1,*%0\n" - : - : "a"(reg_addr), "b"(val), "a"(lock_addr), "b"(key) - ); - - /* in case the hw doesn't reset the lock */ - soc_writel(0, lock_addr); -} - -/* - * Write to a register protected by two lock registers - */ -static void dscr_write_locked2(u32 reg, u32 val, - u32 lock0, u32 key0, - u32 lock1, u32 key1) -{ - soc_writel(key0, dscr.base + lock0); - soc_writel(key1, dscr.base + lock1); - soc_writel(val, dscr.base + reg); - soc_writel(0, dscr.base + lock0); - soc_writel(0, dscr.base + lock1); -} - -static void dscr_write(u32 reg, u32 val) -{ - struct locked_reg *lock; - - lock = find_locked_reg(reg); - if (lock) - dscr_write_locked1(reg, val, lock->lockreg, lock->key); - else if (dscr.kick_key[0]) - dscr_write_locked2(reg, val, dscr.kick_reg[0], dscr.kick_key[0], - dscr.kick_reg[1], dscr.kick_key[1]); - else - soc_writel(val, dscr.base + reg); -} - - -/* - * Drivers can use this interface to enable/disable SoC IP blocks. - */ -void dscr_set_devstate(int id, enum dscr_devstate_t state) -{ - struct devstate_ctl_reg *ctl; - struct devstate_stat_reg *stat; - struct devstate_info *info; - u32 ctl_val, val; - int ctl_shift, ctl_mask; - unsigned long flags; - - if (!dscr.base) - return; - - if (id < 0 || id >= MAX_DEVSTATE_IDS) - return; - - info = &dscr.devstate_info[id]; - ctl = info->ctl; - stat = info->stat; - - if (ctl == NULL) - return; - - ctl_shift = ctl->shift + ctl->nbits * (id - ctl->start_id); - ctl_mask = ((1 << ctl->nbits) - 1) << ctl_shift; - - switch (state) { - case DSCR_DEVSTATE_ENABLED: - ctl_val = ctl->enable << ctl_shift; - break; - case DSCR_DEVSTATE_DISABLED: - if (ctl->enable_only) - return; - ctl_val = ctl->disable << ctl_shift; - break; - default: - return; - } - - spin_lock_irqsave(&dscr.lock, flags); - - val = soc_readl(dscr.base + ctl->reg); - val &= ~ctl_mask; - val |= ctl_val; - - dscr_write(ctl->reg, val); - - spin_unlock_irqrestore(&dscr.lock, flags); - - if (!stat) - return; - - ctl_shift = stat->shift + stat->nbits * (id - stat->start_id); - - if (state == DSCR_DEVSTATE_ENABLED) - ctl_val = stat->enable; - else - ctl_val = stat->disable; - - do { - val = soc_readl(dscr.base + stat->reg); - val >>= ctl_shift; - val &= ((1 << stat->nbits) - 1); - } while (val != ctl_val); -} -EXPORT_SYMBOL(dscr_set_devstate); - -/* - * Drivers can use this to reset RMII module. - */ -void dscr_rmii_reset(int id, int assert) -{ - struct rmii_reset_reg *r; - unsigned long flags; - u32 val; - - if (id < 0 || id >= MAX_SOC_EMACS) - return; - - r = &dscr.rmii_resets[id]; - if (r->mask == 0) - return; - - spin_lock_irqsave(&dscr.lock, flags); - - val = soc_readl(dscr.base + r->reg); - if (assert) - dscr_write(r->reg, val | r->mask); - else - dscr_write(r->reg, val & ~(r->mask)); - - spin_unlock_irqrestore(&dscr.lock, flags); -} -EXPORT_SYMBOL(dscr_rmii_reset); - -static void __init dscr_parse_devstat(struct device_node *node, - void __iomem *base) -{ - u32 val; - int err; - - err = of_property_read_u32_array(node, "ti,dscr-devstat", &val, 1); - if (!err) - c6x_devstat = soc_readl(base + val); - printk(KERN_INFO "DEVSTAT: %08x\n", c6x_devstat); -} - -static void __init dscr_parse_silicon_rev(struct device_node *node, - void __iomem *base) -{ - u32 vals[3]; - int err; - - err = of_property_read_u32_array(node, "ti,dscr-silicon-rev", vals, 3); - if (!err) { - c6x_silicon_rev = soc_readl(base + vals[0]); - c6x_silicon_rev >>= vals[1]; - c6x_silicon_rev &= vals[2]; - } -} - -/* - * Some SoCs will have a pair of fuse registers which hold - * an ethernet MAC address. The "ti,dscr-mac-fuse-regs" - * property is a mapping from fuse register bytes to MAC - * address bytes. The expected format is: - * - * ti,dscr-mac-fuse-regs = <reg0 b3 b2 b1 b0 - * reg1 b3 b2 b1 b0> - * - * reg0 and reg1 are the offsets of the two fuse registers. - * b3-b0 positionally represent bytes within the fuse register. - * b3 is the most significant byte and b0 is the least. - * Allowable values for b3-b0 are: - * - * 0 = fuse register byte not used in MAC address - * 1-6 = index+1 into c6x_fuse_mac[] - */ -static void __init dscr_parse_mac_fuse(struct device_node *node, - void __iomem *base) -{ - u32 vals[10], fuse; - int f, i, j, err; - - err = of_property_read_u32_array(node, "ti,dscr-mac-fuse-regs", - vals, 10); - if (err) - return; - - for (f = 0; f < 2; f++) { - fuse = soc_readl(base + vals[f * 5]); - for (j = (f * 5) + 1, i = 24; i >= 0; i -= 8, j++) - if (vals[j] && vals[j] <= 6) - c6x_fuse_mac[vals[j] - 1] = fuse >> i; - } -} - -static void __init dscr_parse_rmii_resets(struct device_node *node, - void __iomem *base) -{ - const __be32 *p; - int i, size; - - /* look for RMII reset registers */ - p = of_get_property(node, "ti,dscr-rmii-resets", &size); - if (p) { - /* parse all the reg/mask pairs we can handle */ - size /= (sizeof(*p) * 2); - if (size > MAX_SOC_EMACS) - size = MAX_SOC_EMACS; - - for (i = 0; i < size; i++) { - dscr.rmii_resets[i].reg = be32_to_cpup(p++); - dscr.rmii_resets[i].mask = be32_to_cpup(p++); - } - } -} - - -static void __init dscr_parse_privperm(struct device_node *node, - void __iomem *base) -{ - u32 vals[2]; - int err; - - err = of_property_read_u32_array(node, "ti,dscr-privperm", vals, 2); - if (err) - return; - dscr_write(vals[0], vals[1]); -} - -/* - * SoCs may have "locked" DSCR registers which can only be written - * to only after writing a key value to a lock registers. These - * regisers can be described with the "ti,dscr-locked-regs" property. - * This property provides a list of register descriptions with each - * description consisting of three values. - * - * ti,dscr-locked-regs = <reg0 lockreg0 key0 - * ... - * regN lockregN keyN>; - * - * reg is the offset of the locked register - * lockreg is the offset of the lock register - * key is the unlock key written to lockreg - * - */ -static void __init dscr_parse_locked_regs(struct device_node *node, - void __iomem *base) -{ - struct locked_reg *r; - const __be32 *p; - int i, size; - - p = of_get_property(node, "ti,dscr-locked-regs", &size); - if (p) { - /* parse all the register descriptions we can handle */ - size /= (sizeof(*p) * 3); - if (size > MAX_LOCKED_REGS) - size = MAX_LOCKED_REGS; - - for (i = 0; i < size; i++) { - r = &dscr.locked[i]; - - r->reg = be32_to_cpup(p++); - r->lockreg = be32_to_cpup(p++); - r->key = be32_to_cpup(p++); - } - } -} - -/* - * SoCs may have DSCR registers which are only write enabled after - * writing specific key values to two registers. The two key registers - * and the key values can be parsed from a "ti,dscr-kick-regs" - * propety with the following layout: - * - * ti,dscr-kick-regs = <kickreg0 key0 kickreg1 key1> - * - * kickreg is the offset of the "kick" register - * key is the value which unlocks writing for protected regs - */ -static void __init dscr_parse_kick_regs(struct device_node *node, - void __iomem *base) -{ - u32 vals[4]; - int err; - - err = of_property_read_u32_array(node, "ti,dscr-kick-regs", vals, 4); - if (!err) { - dscr.kick_reg[0] = vals[0]; - dscr.kick_key[0] = vals[1]; - dscr.kick_reg[1] = vals[2]; - dscr.kick_key[1] = vals[3]; - } -} - - -/* - * SoCs may provide controls to enable/disable individual IP blocks. These - * controls in the DSCR usually control pin drivers but also may control - * clocking and or resets. The device tree is used to describe the bitfields - * in registers used to control device state. The number of bits and their - * values may vary even within the same register. - * - * The layout of these bitfields is described by the ti,dscr-devstate-ctl-regs - * property. This property is a list where each element describes a contiguous - * range of control fields with like properties. Each element of the list - * consists of 7 cells with the following values: - * - * start_id num_ids reg enable disable start_bit nbits - * - * start_id is device id for the first device control in the range - * num_ids is the number of device controls in the range - * reg is the offset of the register holding the control bits - * enable is the value to enable a device - * disable is the value to disable a device (0xffffffff if cannot disable) - * start_bit is the bit number of the first bit in the range - * nbits is the number of bits per device control - */ -static void __init dscr_parse_devstate_ctl_regs(struct device_node *node, - void __iomem *base) -{ - struct devstate_ctl_reg *r; - const __be32 *p; - int i, j, size; - - p = of_get_property(node, "ti,dscr-devstate-ctl-regs", &size); - if (p) { - /* parse all the ranges we can handle */ - size /= (sizeof(*p) * 7); - if (size > MAX_DEVCTL_REGS) - size = MAX_DEVCTL_REGS; - - for (i = 0; i < size; i++) { - r = &dscr.devctl[i]; - - r->start_id = be32_to_cpup(p++); - r->num_ids = be32_to_cpup(p++); - r->reg = be32_to_cpup(p++); - r->enable = be32_to_cpup(p++); - r->disable = be32_to_cpup(p++); - if (r->disable == 0xffffffff) - r->enable_only = 1; - r->shift = be32_to_cpup(p++); - r->nbits = be32_to_cpup(p++); - - for (j = r->start_id; - j < (r->start_id + r->num_ids); - j++) - dscr.devstate_info[j].ctl = r; - } - } -} - -/* - * SoCs may provide status registers indicating the state (enabled/disabled) of - * devices on the SoC. The device tree is used to describe the bitfields in - * registers used to provide device status. The number of bits and their - * values used to provide status may vary even within the same register. - * - * The layout of these bitfields is described by the ti,dscr-devstate-stat-regs - * property. This property is a list where each element describes a contiguous - * range of status fields with like properties. Each element of the list - * consists of 7 cells with the following values: - * - * start_id num_ids reg enable disable start_bit nbits - * - * start_id is device id for the first device status in the range - * num_ids is the number of devices covered by the range - * reg is the offset of the register holding the status bits - * enable is the value indicating device is enabled - * disable is the value indicating device is disabled - * start_bit is the bit number of the first bit in the range - * nbits is the number of bits per device status - */ -static void __init dscr_parse_devstate_stat_regs(struct device_node *node, - void __iomem *base) -{ - struct devstate_stat_reg *r; - const __be32 *p; - int i, j, size; - - p = of_get_property(node, "ti,dscr-devstate-stat-regs", &size); - if (p) { - /* parse all the ranges we can handle */ - size /= (sizeof(*p) * 7); - if (size > MAX_DEVSTAT_REGS) - size = MAX_DEVSTAT_REGS; - - for (i = 0; i < size; i++) { - r = &dscr.devstat[i]; - - r->start_id = be32_to_cpup(p++); - r->num_ids = be32_to_cpup(p++); - r->reg = be32_to_cpup(p++); - r->enable = be32_to_cpup(p++); - r->disable = be32_to_cpup(p++); - r->shift = be32_to_cpup(p++); - r->nbits = be32_to_cpup(p++); - - for (j = r->start_id; - j < (r->start_id + r->num_ids); - j++) - dscr.devstate_info[j].stat = r; - } - } -} - -static struct of_device_id dscr_ids[] __initdata = { - { .compatible = "ti,c64x+dscr" }, - {} -}; - -/* - * Probe for DSCR area. - * - * This has to be done early on in case timer or interrupt controller - * needs something. e.g. On C6455 SoC, timer must be enabled through - * DSCR before it is functional. - */ -void __init dscr_probe(void) -{ - struct device_node *node; - void __iomem *base; - - spin_lock_init(&dscr.lock); - - node = of_find_matching_node(NULL, dscr_ids); - if (!node) - return; - - base = of_iomap(node, 0); - if (!base) { - of_node_put(node); - return; - } - - dscr.base = base; - - dscr_parse_devstat(node, base); - dscr_parse_silicon_rev(node, base); - dscr_parse_mac_fuse(node, base); - dscr_parse_rmii_resets(node, base); - dscr_parse_locked_regs(node, base); - dscr_parse_kick_regs(node, base); - dscr_parse_devstate_ctl_regs(node, base); - dscr_parse_devstate_stat_regs(node, base); - dscr_parse_privperm(node, base); -} |